If you have a calculator, you can use the inverse cos " cos⁻¹ " key. Many upper level books write that as Arccos so as not to confuse you with a negative exponent. We do that because if you take the cosine of any angle, and then the inverse cosine of any angle, it leads you back to the original angle. Think of it as a big "UNDO" button.
To one decimal place, that result is 61.6 degrees.
For the text answers:
conditional - If 2 lines are supplementary then the measure of the angles sum is 180
converse - If the measure if the angle sum is 180 then the 2 lines are supplementary
inverse - If 2 lines are not supplementary then the measure if the angle sum is not 180
contrapositive - If the measure if the angle sum is not 180 then 2 lines are not supplementary.
answer to the picture one:
conditional - If you do all your math homework then you will do well on the test.
converse - If you do well on the test then you do all your math homework
inverse - If you do not do all your math homework then you will not do well on the test.
contrapositive - If you do not well on the test then you did not do all your math homework
D I think. Hope this helps.
X = 19.
Explanation:
This expression is vertical from the angle 135, meaning it is congruent. With that being said, we would need to find what 7 multiplies by to give us 2 less than 135, which would be 133. Because 133 divided by 7 equals 19, x = 19. If we plug this in, we get the following equation: 7(19) + 2 = 135.
Consider one pyramid
Side length of base = 1.5cm and its height is 1 cm
Slant height of one of the lateral faces = sqrt(1^2 + 0.75^2) = 1.25 cm
Area of one of the triangular faces = 0.5 * 1.5* 1.25 = 0.9375 cm^2
There are 8 of these so the required surface area = 8 * 0.9375
= 7.5 cm^2 Answer