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Use substitution to solve the system.

-4x+5y = -26

y = 3x-14

User Afarley
by
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1 Answer

5 votes

Answer:

x= 4, y= -2

Explanation:

To solve the system by substitution, start by labelling the two equations:

-4x +5y= -26 -----(1)

y= 3x -14 -----(2)

Since the second equation already has y as the subject of formula, we can substitute equation (2) into (1). This means that we can replace all the 'y's in equation (1) with 3x -4, such that equation (1) will only be in terms of x.

Substitute (2) into (1):

-4x +5(3x -14)= -26

Expand:

-4x +15x -70= -26

11x= 70 -26

11x= 44

Divide both sides by 11:

x= 44 ÷11

x= 4

Substitute x= 4 into (2):

y= 3(4) -14

y= 12 -14

y= -2

User Mohsen Heydari
by
4.1k points