Answer:
see explanation
Step-by-step explanation:
∠ PQX = 90° ( angle in a semicircle )
∠ PXQ = 42° ( alternate angle theorem )
Angle between tangent and diameter is right, thus
∠ XPQ = 90° - 42° = 48°
To solve this, what you will need to do is find the solution of one variable and then substitute it and solve for the other.
Here’s how to solve:
y+2x=4
-2x -2x
y=4-2x
4-2x + 2x =4
4=4
So if you’re trying to see if it is true, then your answer is that it’s true.
If you’re trying to find the linear equation, then your answer is y=-2x+4.
Use the identity: 
and solve for 
. You get: 
Do the substitution on the left side to get:
