Solve the system by substitution 4x+4y= 12 and x+2y=11

Mathematics

1 answer:

Reika [66]3 years ago

4 0

Answer:

x = -5 and y = 8

Step-by-step explanation:

To solve the system by substitution, solve one equation for a variable. Then substitute the equation into the other equation.

x + 2y = 11 becomes x = 11 - 2y

Substitute x = 11 -2y into 4x + 4y = 12.

4(11-2y) + 4y = 12

44 - 8y + 4y = 12

44 - 4y = 12

32 = 4y

y = 8

Substitute again with y = 8 into the equation to find x.

x = 11 - 2(8)

x = 11 - 16

x = -5

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