Plzzz Help with number 139 don’t understand
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2a + 2s = 32, 6a + 7s = 106
Solve for a in the first equation.
2a = 32 - 2s
a = 16 - s
Substitute a into the second equation.
6(16 - s) + 7s = 106
96 - 6s + 7s = 106
96 + s = 106
s = 10
Substitute s into the first equation.
2a + 2(10) = 32
2a + 20 = 32
2a = 12
a = 6
a = 6, s = 10