Test 10 – Question 30

Posted: November 11, 2020

For question 5 on page 242(Angles, Triangle and Polygons)…

Posted: August 3, 2020

For question 5 on page 242(Angles, Triangle and Polygons), could you explain why the triangle was put into 60,30,90 right triangle and how you came up with b/2 *square root of 3 as the height?

A triangle with angle measures 30°, 60°, 90° has a perimeter of 18+6√3…

Posted: August 8, 2019

A triangle with angle measures 30°, 60°, 90° has a perimeter of 18+6√3. What is the length of the longest side of the triangle?

Thomas is making a sign in the shape of a regular hexagon with 4-inch sides…

Posted: February 20, 2019

Thomas is making a sign in the shape of a regular hexagon with 4-inch sides, which he will cut out from a rectangular sheet of metal. What is the sum of the areas of the four triangles that will be removed from the rectangle?

In the xy-plane what is the slope of the line that passes through the origin and makes a 42° angle with the positive x-axis? A. 0.67 B. 0.74 C. 0.90 D. 1.11

Posted: October 12, 2018

Trigonometry does the trick here. Below is that line making a 42° angle with the positive x-axis. I’ve also drawn a dotted segment to make myself a neat little right triangle. Remember that slope is rise over run—how high the line climbs divided by how far it travels right. In this case, the dotted segment (more…)

sin (90-x) = 12/13 what is the value of sin x?

Posted: August 12, 2018

Think of a 5-12-13 triangle (that’s one of the Pythagorean triples you should know). Say angle A measures x°, which would make angle C measure (90 – x)°. (I’m choosing those based on the fact that I already know that the sine of angle C will be 12/13.) Now that we’ve got it set up, all we (more…)