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Number 2

Topic : Linear Equations with Two Variables

Given the equations
7x + 11y = 141
8x - 12y = -60
Determine the value of x² + 2y!​​

User Tommy King
by
8.3k points

1 Answer

1 vote

Answer:

54

Explanation:

7x + 11y = 141 eq.1

8x - 12y = -60 eq.2

multiply eq.1 by -8 and eq.2 by 7 to eliminate x

-8(7x + 11y = 141) -56x - 88y = -1128 eq.3

7(8x - 12y = -60) 56x - 84y = -420 eq.4

add equations 3 & 4

-172y = -1548

y = 9

substitute y = 9 to any of the equations, to get the value of x

I use equation 1

7x + 11y = 141

7x + 11(9) = 141

7x + 99 = 141

7x = 42

x = 6

Determine the value of x² + 2y

6² + 2(9) = 36 + 18 = 54

User Rulas
by
8.7k points