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2 years ago

Solve the following: a. 4x^2 + 5x + 3 = 2x^2 − 3x b. c^2 − 14 = 5c

Mathematics

1 answer:

Jet001 [13]2 years ago

7 0

Answer:

(a) x = -0.418 , -3.581

(B) c = 6.855, -1.855

Step-by-step explanation:

(A) We have given equation $4x^2+5x+3=2x^2-3x$

$2x^2+8x+3=0$

On comparing with standard quadratic equation $ax^2+bx+c$

a = 2, b = 8 and c = 3

So roots of the equation will be $x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}=\frac{-8\pm \sqrt{8^2-4\times 2\times 3}}{2\times 2}=\frac{-8\pm 6.324}{4}=-0.418,-3.581$

(b) $c^2-14=5c$

$c^2-5c-14=0$

a = 1, b = -5 and c= -14

So $c=\frac{-b\pm \sqrt{b^2-4ac}}{2a}=\frac{-(-5)\pm \sqrt{(-5)^2-4\times 1\times (-14)}}{2\times 1}=\frac{5\pm 8.71}{2}=6.855,-1.855$

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A software designer is mapping the streets for a new racing game. all of the streets are depicted as either perpendicular or par

ElenaW [278]

The equation of the central street PQ is -1.5x - 3.5y = -31.5 option (b) is correct.

<h3>What is a straight line?</h3>

A straight line is a combination of endless points joined on both sides of the point.

We have a straight line:

$-7x+3y=-21.5$

Convert it to the general form given below:

$\rm y=mx+c$

$\rm 3y=-21.5+7x\\\\ \rm y = \frac{-21.5}{3}+\frac{7}{3}x$ or

$\rm y = \frac{7}{3}x-\frac{21.5}{3}$

$m = \frac{7}{3}$ (Slope of AB line)

For the slope(m') of the PQ line:

$\rm m'=-\frac{1}{m}$ ( because AB and PQ are perpendicular to each other)

$\rm m' = -\frac{3}{7}$

We know the:

$\rm (y-y')=m'(x-x')$

Where (x', y') = (7, 6), we get:

$\rm (y-6)=-\frac{3}{7} (x-7)$

$\rm 7(y-6)=-3 (x-7)\\\\\rm 7y-42= -3x+21\\\\\rm 7y= -3x+21+42\\\\\rm 3x+7y=63$

$\rm -1.5x-3.5y=-31.5$ (multiply by -1/2 on both sides)

Thus, the equation of the central street PQ is -1.5x - 3.5y = -31.5

Learn more about the straight line.

brainly.com/question/3493733

6 0

1 year ago

school teacher and needs 22 pieces of wood, 3 over 8 ft long, for a class project. If he has a 9-ft board from which to cut the

tiny-mole [99]

Answer:

Yes, he will have enough 3 over 8 ft pieces for his class.

Step-by-step explanation:

Given:

Number of wood required = 22

Length of each wood, $l=\frac{3}{8}\textrm{ ft}$

Total length of the board, $L=9\textrm{ ft}$

Therefore, the number of woods that can be made using the given board is given as:

$\textrm{Number of woods made}=\frac{\textrm{Total length of board}}{\textrm{Length of each wood}}\\\textrm{Number of woods made}=\frac{L}{l}=\frac{9}{\frac{3}{8}}=9\times \frac{8}{3}=\frac{72}{3}=24$

So, he can make 24 woods of length $\frac{3}{8}\textrm{ ft}$ using the 9 ft board. But he has to make only 22 pieces.

Therefore, he has enough of the wood to make the required number of pieces.

3 0

2 years ago

Algebraically prove that X^3+10/x^3+9=1+ 1/x^3+9 where x is not equal to -3

ehidna [41]

<span>Algebraically prove that X^3+10/x^3+9=1+ 1/x^3+9 where x is not equal to -3
</span> $\dfrac{x^3+10}{x^3+9}=1+\dfrac{1}{x^3+9} \\ \\ \\ \dfrac{x^3+10}{x^3+9}=\dfrac{(x^3+9)+1}{x^3+9}\\ \\ \\ \dfrac{x^3+10}{x^3+9}=\dfrac{x^3+10}{x^3+9} \\ \\ \\x\in R \qquad x\in (-\infty, +\infty)$ <span>
</span>

7 0

3 years ago

The Super Bounce brand of bouncy balls rebounds to 85% of the height from which it was dropped. Write both the explicit and recu

jarptica [38.1K]

Answer:

Explicit formula is $h(n)=4(0.85)^{n-1}$ .

Recursive formula is $h_n=0.85h_{n-1}$

Step-by-step explanation:

Step 1

In this step we first find the explicit formula for the height of the ball.To find the explicit formula we use the fact that the bounces form a geometric sequence. A geometric sequence has the general formula , $a_{n+1}=ar^{n-1}.$ In this case the first term $a_o=4$ , the common ratio $r=0.85$ since the ball bounces back to 0.85 of it's previous height.

We can write the explicit formula as,

$h(n)=4(0.85)^{n-1}.$

Step 2

In this step we find the recursive formula for the height of the ball after each bounce. Since the ball bounces to 0.85 percent of it's previous height, we know that to get the next term in the sequence, we have to multiply the previous term by the common ratio. The general fomula for a geometric sequene is $a_n=a_{n-1}\times r.$