Question 1129393
y = x+11
2(y+x) = 10 substitute y with equivalent above:
2(x+11+x) = 10
2x+22+2x = 10
4x = -12
x = -3
and
y = x+11 = -3+11 = 8
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Check:
Twice the sum of the two numbers is 10
2(8+-3)= 16+-6 = 10 Correct