Please help me and explain how to do it
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Answer:
<A = 50
Step-by-step explanation:
The sum of the angles of a triangle are 180
<A + <B + <C = 180
2x-10 + 70 + x+30 = 180
Combine like terms
3x +90 = 180
Subtract 90 from each side
3x+90-90 = 180-90
3x= 90
Divide each side by 3
3x/3 =90/3
x = 30
We want <A = 2x-10
=2(30)-10
=60-10
=50