Solve the system by substitution. −7x−10y= 40 x=−2y

Mathematics

1 answer:

Harrizon [31]3 years ago

5 0

Answer:

x= -20, y= 10

Step-by-step explanation:

Label the two equations:

-7x -10y= 40 -----(1)

x= -2y -----(2)

Substitute (2) into (1):

-7(-2y) -10y= 40

Expand:

14y -10y= 40

Simplify:

4y= 40

Divide both sides by 4:

y= 40 ÷4

y= 10

Substitute y= 10 into (2):

x= -2y

x= -2(10)

x= -20

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