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nasty-shy [4]
3 years ago
11

Please help I don't understand 120 - 28a = 78

Mathematics
2 answers:
stiks02 [169]3 years ago
6 0
Simplifying
120 + -28a = 78

Solving
120 + -28a = 78

Solving for variable 'a'.

Move all terms containing a to the left, all other terms to the right.

Add '-120' to each side of the equation.
120 + -120 + -28a = 78 + -120

Combine like terms: 120 + -120 = 0
0 + -28a = 78 + -120
-28a = 78 + -120

Combine like terms: 78 + -120 = -42
-28a = -42

Divide each side by '-28'.
a = 1.5

Simplifying
a = 1.5
Gemiola [76]3 years ago
4 0
120 - 28a = 78
28a = 120-78
28a = 42
a =  \frac{42}{28}  \\ a =  \frac{3}{2}
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