How do I find the value of the unknown variable
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6x + 2 + 40 = 90
Let x = the unknown
6x + 42 = 90
6x = 90 - 42
6x = 48
x = 48/6
x = 8
Answer:
x=8
Step-by-step explanation:
We know that 40 + (6x+2) +90 = 180 since the three angles form a straight line
40 + (6x+2) +90 = 180
Combine like terms
132 + 6x = 180
Subtract 132 from each side
132-132 +6x= 180-132
6x = 48
Divide each side by 6
6x/6 = 48/6
x = 8