Question

The second angle of a triangle is five times as large as the first. The measure

of the third angle is 12 degrees greater than that of the first angle. What is
the measurement of the largest angle?

Answer 1

120

Explanation:

consider
1st angle= a
2nd angle = b
3rd angle = c

now,
b=5a ............. equation 1
c = a+12 ........ equation 2

as we know in a triangle, sum of all angle is 180.

so
a+b+c = 180
=> a +5a + (a+12 ) = 180
=> 7a = 180-12 =168
=> a = 168/7 = 24

so a= 24
b = 5(24) = 120
c = a+12 = 24+12 =36

so b = largest = 120