Question

How do you solve 5 = y - x and 4x2=−17x+y+4?

Answer 1

will let you finish the calculation

Explanation:

Given:

5=y−x .......................Equation(1)

4x2=−17x+y+4 ......Equation(2)

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Consider equation(1)

Add x to both sides.

5+x=y−x+x

5+x=y ......................Equation(1a)

Using Equation(1a) substitute for y in Equation(2)

4x2=−17x+y+4 → 4x2=−17x+5+x+4

→ 4x2=−16x+9

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Now we have a quadratic equation

4x2=−16

Answer 2

If y-x=5

then y=5+x

4x^2 = -17x + y + 4

-( -4x^2 - 17x +x + 5 + 4 = 0)

(4x^2 + 16x - 20 = 0) ÷ 4

x^2 + 4x - 5 = 0

x^2 + 5x - x - 5 = 0

x(x + 5) -1(x + 5) = 0

(x + 5)(x -1) = 0

Therefore, x = -5, 1