Question

SUPER URGENT!!!!!!!! I NEED HELP!!!!!1 PLSSSS!!!!!Use the linear combination method to solve the system of equations. Explain each step of your solution. 3x-8y=7" " " " x+2y=-7

Answer 1

Answer:

x=-3,y=-2

Step-by-step explanation:

Given 2 expressions

S1:$3x-8y=7$

S2:$x+2y=-7$

Write one equation in terms of any variable (x or y)

Here I am writing S1 in terms of y

$3x-8y=7\\3x-7=8y\\y=\frac{3x-7}{8}$

Substitute this value of y as the value of y in S2

⇒$x+2y=-7\\x+(\frac{3x-7}{8} )\times2=-7\\8x+6x-14=-56\\14x=-42\\x=-3$

Therefore $x=-3$

Substitute this value of x in any of the expressions S1 or S2

Here i am substituting in S2

⇒$x+2y=-7\\-3+2y=-7\\2y=(-7+3)\\2y=-4\\y=-2$

Therefore x=-3 and y=-2