B: z=80___________________________________
Y=x-4
x=y+4
y=-3(y+4)
y=-3y-12
4y=-12
y=-3
x=1
Remember: when calculating percent it will always be over 100. With the given numbers 14 is your part out of the total (25). It should be written as part/whole.
As previously said, the percent is always over 100. (x/100)
In this problem you are given the part (14) and the whole (25). So it would be 14/25. The percent in this problem would be x/100. Now to find percent with the given part/whole, you would multiply 14 with 100. Then simply divide by 25.
The area of a triangle is A=1/2b*h
You have the base (b) and you have the area (A)
So, if you plug in what you know, you get this:
45.5=1/2*10*h
Simplify it:
45.5=5h
Now solve for h
Divide by 5 to get h alone:
9.1=h
Your height is 9.1cm
Hope this helps :)