The sum of the measures of the angles below is 180∘. A triangle is shown. The first angle measures x degrees. The second angle measures two x minus ten degrees. The third angle measures x plus ten degrees. What is the measure of each angle? Write and solve an equation.

Evaluate cos2θ for cosθ = square root of 3/2

Ineed me i stuck and i don’t want to get it wrong

Statement reason 1. δabc is similar to δced. given 2. 3. definition of slope 4. slope of slope of definition of slope 5. slope of × slope of multiplying the slopes 6. slope of × slope of substitution property of equality 7. slope of × slope of simplifying the right side the table contains the proof of the relationship between the slopes of two perpendicular lines. what is the reason for statement 2? a. parallel line segments that meet a common perpendicular line are proportional in length. b. the lengths of vertical and horizontal sides in congruent triangles are in a common ratio. c. trigonometric identities determine the lengths of the legs in a right triangle. d. corresponding side lengths in similar triangles are proportional in length.