(a) the given triangle is a isosceles triangle, therefore the two leg sides will be congruent, as well as the two base angles. It is given that one of the base angles ∠XYW is 70°, therefore, due to the law of a isosceles triangle, the measurement of ∠XWY is also 70°. Remember, a triangle's interior angles add up to 180°, so:
180 - (70 + 70) = 180 - 140 = 40
40° is your answer.
m∠X = 40°
(b) All sides are congruent, making it a equilateral triangle. If it is a equilateral triangle, then all the angles also have the same measurement. The total of the interior angle's measurement is 180°. Divide by the amount of angles, 3:
180/3 = 60
60° is your answer.
m∠V = 60°
~
The everyone of two longer parts has 57 cm length and the shortest part has 42 cm length.
less 30cm from 156 and divide the remain amount of 126 into three parts. The answer will be 42 cm, then add 15,15 in longer parts.
First set up the equation 12x-7=4x+9
Get all the x's on one side and number on one side so you have 8x= 16
You get X=2