3x+6y=21 and 5x+8y=31 what does x and y equal

Question

Give me the steps for this problem

Answer 1

Elimination method

3x+6y = 21

Divide to each side by 3.

x+2y = 7

Multiple to each side by 5.

5x+10y = 35 -------> (1)

5x+8y = 31 -----------> (2)

To eliminate the x value, subtract equation (2) from equation (1).

5x+10y = 35

5x+8y = 31

(-) (-)    (-)

_________

2y = 4

Divide to each side by 2.

2y/2 = 4/2

⇒ y = 2

Substitute the y value in (2).

5x+8*2 = 31

5x+16 = 31

Subtract 16 from each side.

5x+16-16 = 31-16

5x = 15

Divide to each side by 5.

5x/5 = 15/5

⇒ x = 3

Solutin x = 3, y = 2.

x,y are not equal.