B + (-2) = 0
Here, we need to do the inverse operation, and apply it to BOTH sides of teh equation.
b -2 = 0
+2 +2
b = 2
Now we have our answer, b = 2
Final answer: b = 2
sum of two angles of triangle are equal to the exterior angle of triangle
Again, nice problem. These are not super easy. You need to imagine the triangles in the figure and relate sides.
For instance: ADC, its hypotenuse is 15
For ABC, it is 20,
so 20/15 is the ratio between both triangles. Now let's choose the side with 'x'
x is one side of ADC, the corresponding side in ABC is 15 (the second longest sides). You need to rotate the triangles, etc ... That's the tricky part :)
So:
20/15 =15/x ----> x = 15*15/20 = 225/20 = 45/4
Which is C
Not sure whether it's too late to help you though!!!!
Also notice that it's kind of a product rule:
x * 20 = 15 * 15
I am sure the book explains a short way of getting to this equation, like sides opposite, blah blah, but what i told you is the reason. You asked for understanding it! Best luck!
Answer:
f(8)=20..The answer is 8 :)
