Question 405927
"The second angle of a triangle is twice as large as the first angle. The third angle is 12degrees more than four times the first angle. How large are the angles?"


x = first angle
2x = second angle {second angle is twice as large as first}
4x + 12 = third angle {twelve more than four times the first}


All angles of a triangle add up to 180.


x + 2x + 4x + 12 = 180 {added up all angles and set equal to 180}
7x + 12 = 180 {combined like terms}
7x = 168 {subtracted 12 from both sides}
x = 24 {divided both sides by 7}
2x = 48 {substituted 24, in for x, into 2x}
4x + 12 = 108 {substituted 24, in for x, into 4x + 12}


24, 48, and 108 are the angles

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