Answer:
AA similarity postulate
Explanation:
For triangle XZY, the angles are 90°, 40°, 50°.
For triangle AXB, the angles are 90°, 40°, 50°.
Which states that all the angles are of equal measure in the triangles.
This is stated by AA similarity theorem meaning when two angles are equal in the triangle. Then the triangles are congruent to each other.
A direct variation is a mathematical relationship between two variables that can be expressed by an equation in which one variable is equal to a constant times the other. In other words, a direct variation is where

.
In answer a,

, so it is a direct variation.
In answer c,

, so it is a direct variation.
In answer d,

, so it is a direct variation,
Only answer b is left, which means the answer must be 'b'.
We also know 'b' is the answer because it cannot be expressed as <span>

. Instead, it is expressed as </span>

, which is not the same thing and is therefore not a direct variation.
Hope I helped, and let me know if you have any questions :)
Answer: R=8
Step-by-step explanation: R-7=1, R+7=1+7, R=8.
Answer:
Step-by-step explanation:
first your going to do the least common multiple which is 12 for both then your going to subtract because were trying to find out how many students did there work correctly. so, whatever you do to the denominator you do to the numerator so, its going to be 10/12 - 9/12= 1/12 is your answer.