Find the value of x.
70
20
38
55
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Answer:
x = 20
Step-by-step explanation:
Since one part of the straight angle = 90°, then
4x - 10 + x = 90, that is
5x - 10 = 90 ( add 10 to both sides )
5x = 100 ( divide both sides by 5 )
x = 20