All categories

2 years ago

PLS HELP WILL MARK BRAINLIEST!!!!!!!! answer both questions (they are two separate questions)

Mathematics

1 answer:

Angelina_Jolie [31]2 years ago

5 0

Answer A is correct for both questions.

Step-by-step explanation:

The area of the rectangle is lengthxwidth. To find the length, we can divide the area by the width.

$\frac{(4x^2-43x+63)}{(4x-7)}$ is the equation.

We need to simplify it (or just divide). Since the coefficient of the area (on the x^2) is the same as that on the width, we know that that same coefficient on the length is 1.

This gets us to the basic frame (1x+/-y).

To find the value of y, we need to pay attention to the "-43x+63" and "-7" aspects of the area and width, respectively. To get "63," the "-7" was multiplied by the y — by dividing 63 by -7, we know that the value of y is -9 (the numbers both have to be negative to multiply to a positive number).

We are left with the length (x-9). Put together, this means (x-9)(4x-7) is the area. Multiplying, that makes (4x^2-7x-36x+63), or (4x^2-43x+63). Since this is the area given to us, we know our answer is correct. For this question, the answer is A.

*****

Divide $9x^4-2-6x-x^2$ by $3x-1$ . First, put the first equation in order by exponents. We get $\frac{9x^4-x^2-6x-2}{3x-1}$ . Since the exponent on the upper equation goes up to x^4, and we are dividing by a simple x, we know that the first exponent in our answer will be x^3. Since our coefficient needs to have a product of 9 when multiplied by 3, it is 3. The first part of our answer is $(3x^3)$ . Since there is no exponent of 3 for x in the upper equation, and since the "x^2" that has to be the next term in the equation due to it being present in each answer choice, we know that it as to be a "+x^2" — the "3x^3 that result from the "-1" (in the lower equation) being multiplied by 3x^3 have to be cancelled out by a "-3x^3", and if the sign for the term "x^2" is negative, we end up with tw0 "3x^3" that add up to "6x^3" instead of cancelling each other out.

Now, we have $(3x^3-x^2)$ . We can immediately rule out C. Moving on.

We now have $(3x-1)(3x^3+x^2)=9x^4-x^2$ . We can rule out answer choice B because it is incomplete - we are missing the second part of the upper equation, "-6x-2." Both of the remaining answers include "-2" as the next term, whether with an x or without.

Honestly, I haven't done algebra in a few years — while I know there's a way to deduce the rest of the equation, let's solve the equation using the two remaining answer choices and see which one is correct.

A: $(3x-1)(3x^3+x^2-2-\frac{4}{3x-1} )$

$=9x^4+3x^3-6x -3x^3-x^2+2-4$ (FOIL) (3x-1 times $-\frac{4}{3x-1}$ = -4)

$=9x^4+3x^3-3x^3-x^2-6x+2-4$ (in order of exponents)

$=9x^4-x^2-6x+2-4$ (simplify)

$=9x^4-x^2-6x-2$ (simplify)

D: $(3x-1)(3x^3+x^2-2x-\frac{4}{3x-1} )$

$=9x^4+3x^3-6x^2-\frac{4}{1} -3x^3-x^2+3x+\frac{4}{1}$ (FOIL)

$=9x^4+3x^3-3x^3-7x^2-4+4$ (in order of exponents)

$=9x^4-7x^2$ (simplify)

A is exactly the long fraction we started with ( $9x^4-2-6x-x^2$ ), just in a different order! This means that answer A, when multiplied by (3x-1), equals the same thing which, if divided by (3x-1), yields answer A. Because of the rules of multiplication/division (xy=z, z/x=y, z/y=z), this means that we have the proper set of numbers. Answer A is correct.

I hope this helps!!!!! Let me know if there's anything else I can help with :)

You might be interested in

Please help.. nobody will help me and I’ve been asking this question so many times but nobody will answer..

lisov135 [29]

Answer:

The floor covers $81yd^{2}$

Step-by-step explanation:

This question is actually easier than you think, but I am here to help.

First off you know the room is a square. All squares have equal sides no matter what, that is the number 1 basic rule. (27ft by 27ft)

1. Find the area of the square: To find area you multiply Length by Width. Since you are multiplying two units you will get a squared value. The square measures 27 ft by 27 ft on both sides.

Lets multiply those two numbers:

$(27 * 27) = 729ft^{2}$

We need to stay in the same unit because you are multiplying two values of the same unit. The total square feet of the room is $729ft^{2}$

2. Next, all you need to do is convert $ft^{2}$ to $yd^{2}$

Like you mentioned: $(1 yd^{2} = 9ft^{2})$

Now lets create a proportion between the two unit:

$\frac{729ft^{2} }{1} * \frac{1yd^{2} }{9ft^{2} }$

The $ft^{2}$ unit cross cancels and your left with $yd^{2}$ .

Now all you do is multiply straight across and you get $\frac{729yd^{2} }{9} = 81 yd^{2}$

5 0

4 years ago

What is the value of x? Enter your answer in the box. x =

andreev551 [17]

The two angles form a straight line which equals 180 degrees:

10x-20 + 6x + 8 = 180

Combine like terms:

16x -12 = 180

Add 12 to both sides:

16x = 192

Divide both sides by 16:

X = 192/16

X = 12

7 0

3 years ago

1. Assume the reserve requirement is 10%. First National Bank receives a deposit of $5,400. If there is no slippage, how much co

Andru [333]

Compose the result function for 400 by replacing the function designators with the actual functions 400

3 0

4 years ago

A catapult launches a boulder with an upward velocity of 92 m/s. the height of the boulder, h, in meters after t seconds is give

omeli [17]

Check the picture below.

$\bf \textit{vertex of a vertical parabola, using coefficients}
\\\\
h=\stackrel{\stackrel{a}{\downarrow }}{-5}t^2\stackrel{\stackrel{b}{\downarrow }}{+92}t\stackrel{\stackrel{c}{\downarrow }}{+16}
\qquad \qquad 
\left(-\cfrac{ b}{2 a}~~~~ ,~~~~ c-\cfrac{ b^2}{4 a}\right)$

$\bf \left( -\cfrac{92}{2(-5)}~~,~~16-\cfrac{92^2}{4(-5)} \right)\implies \left(\cfrac{46}{5}~~,~~16+\cfrac{2116}{5} \right)
\\\\\\
\left(\cfrac{46}{5}~~,~~\cfrac{2196}{5} \right)\implies \left(\stackrel{\textit{how long it took}}{9\frac{1}{5}}~~,~~\stackrel{\textit{how high it went}}{439\frac{1}{5}} \right)$