Question

What are the solutions to the system of equations? {y=x²−4x+8 y=2x+3

Answer 1

Answer:

x = 1, y = 5

x = 5, y = 13

Step-by-step explanation:

y = x² − 4x + 8 .......(1)

y = 2x + 3 .......(2)

Substitute the value of y in equation 2 into equation 1

y = x² − 4x + 8

y = 2x + 3

x² − 4x + 8 = 2x + 3

Rearrange

x² − 4x − 2x + 8 − 3 = 0

x² − 6x + 5 = 0

Solve by factorization

Find the product you x² and 5. The result is 5x²

Find the factors of 5x² such that their sum will result in −6x. The factors are −x and −5x.

Replace −6x in the equation above with −x and −5x. This is illustrated below:

x² − x − 5x + 5 = 0

x(x − 1) − 5(x − 1) = 0

(x − 1)(x − 5) = 0

x − 1 = 0 or x − 5 = 0

x = 1 or x = 5

Substitute the value of x into equation 2 to obtain the value of y.

y = 2x + 3

x = 1

y = 2(1) + 3

y = 2 + 3

y = 5

x = 5

y = 2x + 3

y = 2(5) + 3

y = 10 + 3

y = 13

SUMMARY:

x = 1, y = 5

x = 5, y = 13