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3 years ago

How do i factor -7x^2+5x+12

Mathematics

1 answer:

yKpoI14uk [10]3 years ago

6 0

Answer:

-(x + 1)(7x - 12)

Step-by-step explanation:

Step 1: Factor out a -1

-1(7x² - 5x - 12)

Step 2:

Think. Answer this question: "What 2 numbers multiply up to -12 and adds up to -5 while 7 is an x coefficient?". You answer should be -12 and 1.

So, <em>factor</em>.

-1(x + 1)(7x - 12)

To double check, just expand/FOIL everything and see if it is the same as the original expression.

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Lucy cuts 4 squares with side length x in. from the corners of a 6 in. by 9 in. cardboard rectangle. She folds the remaining car

nikdorinn [45]

Answer:

you can use the same type of power to make it easier

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3 years ago

Joni has a circular garden with a diameter of 16.5. If she uses 2 teaspoons of fertilizer for every 25 square feet of garden how

Murljashka [212]

Answer:

17.106 Teaspoons of fertilizer

Step-by-step explanation:

Joni has a circular garden with a diameter of 16.5. If she uses 2 teaspoons of fertilizer for every 25 square feet of garden how many teaspoons of fertilizer will Joni need for her entire garden?

Step 1

We calculate the area of the garden.

The garden is circular in shape.

Area of a circle = πr²

r = radius = Diameter/2

Diameter = 16.5 ft

r = 16.5/2

r = 8.25 ft

Area of the circle = π × 8.25²

Area of the circle (Garden) = 213.82464998 ft²

Approximately = 212.825ft²

Step 2

If she uses 2 teaspoons of fertilizer for every 25 square feet of garden how many teaspoons of fertilizer will Joni need for her entire garden?

25 ft² = 2 teaspoons of fertilizer

212.825ft² = x

Cross Multiply

25 ft² × x = 212.825ft² × 2

x = 213.825× 2/25 ft²

x = 17.106 Teaspoons of fertilizer

3 0

3 years ago

the height of scale model building is 15 in. the scale is 5 in. to 32 i. find the height of the actual building in inches and in

zheka24 [161]

Inches =15,feet =180

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3 years ago

Read 2 more answers

What is the length of each leg of the triangle below?

iragen [17]

Answer:

option A

Step-by-step explanation:

since the given triangle is an isosceles triangle it's two remaining sides are equal

let the length of missing side be x

using pythagoras theorem

a^2 + b^2 = c^2

x^2 + x^2 = 22^2

2x^2 = 484

x^2 = 484/2

x = $\sqrt{242}$

x = $11\sqrt{2}$

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3 years ago

Factor: a) 4x^2-13x+9

Fittoniya [83]

Answer:

A. $x = \frac{9}{4}$

B. $x = 1$

Step-by-step explanation:

I don't know if you know this method. I'll explain.

1. Rewrite the same expression, but multiplied and divided by the same number that has the squared variable.

$4(\frac{4x^2-13x+9}{4})$

2. Take this expression to the expression $x^{2} +bx+c$ , you can do this by grouping. (4)( $4x^{2}$ ) can be grouped as $(4x)^2$ ; since what we want is to keep the (4x) in parenthesis, we don't multiply by 13. leaving it like 13(4x). Finally, we multiply 4 * 9 = 36. The denominator remains. Leaving the expression like:

$\frac{(4x)^2-13(4x)+36}{4}$

So you see, we now have the expression $x^2+bx+c$

$x^{2} =(4x)^{2}$

$bx = -13(4x)$

$c = 36$

3. Solve the expression by making 2 parenthesis, extracting (4x) and putting it into both of them like so.

(4x) (4x)

The sign in the first parenthesis is going to be the same as the second number; in this case, negative.

(4x -) (4x)

The sign in the second parenthesis is going to be the multiplication of the second and third signs in front of the numbers. In this case (-) (+) = -

(4x -) (4x -)

Next, we have to find a number that multiplied by another number be equal to ''c'' and added up or substracted (depending on the signs) be equal to ''b''. In this case, since we have the same signs in both parenthesis, we must only find a number which multiplied by another number be equal to 36 and substracted by that number be equal to 13. These two numbers are: 9 and 4 because 9 * 4 = 36 and - 9 + (-4) = -13

Remember that everything is being divided by 4 in this problem.

$\frac{(4x-9)(4x-4)}{4}$

4. Factor. If you have done everything correctly, the factor number will be the same as the one in the denominator. In this case, it's 4.

$(4x-4)$ is factorable. Their common factor number is 4. If you do not remember how to factor, it's basically dividing by a common number or variable.