Question

The sides of an isosceles triangle are 5, 5, and 7. Find the measure of the vertex angle to the nearest degree.

Answer 1

@perl

Answer 2

@luckycoins888

Answer 3

you can law of cosines

Answer 4

Let me get the equation started

5^2 + 5^2 - 2*5*5cos(theta) = 7^2

Answer 5

49?

Answer 6

not quite, did you solve that?

Answer 7

5^2 + 5^2 - 2*5*5cos(theta) = 7^2
25 + 25 - 50 cos(theta) = 49

50 - 50*cos(theta) = 49

-50cos(theta) = 49 - 50

-50*cos(theta) = -1

cos(theta) = 1/50

Answer 8

thnx