Let number of polio vaccination be x and mesles vaccination be y
from question x+y=60 and 4x+2y= 184
from both equation x =32 and y=28
Y=(x3)2
if x=5
y=(5.3)2
=(15)2
=30
So your equation is y = x² - 20x + 15. what you'll want to do is complete the square, so take half of 20 and square it. 20/2 = 10. 10² = 100. add 100 to both sides. and simplify x²-20x+100+15 to (x²-10)²+15. now subtract 100 from both sides to get y alone. this leaves you with y = (x²-10)-85. that's your vertex form.
The answer to the problem is C.
When solving these types of problems just ignore the “shorter leg” or “longer leg” and focus on the lengths. Pythagorean’s Theorem is used in this problem. Since a leg and hypotenuse length are given then you you set the problem up as 9^2+b^2=15^2. You then do the squares so that it is shown as this, 81+b^2=225. Next you need to subtract 81 on both sides of the equation to isolate the variable b (or the missing leg length) which leaves you with b^2=144. Next to isolate the variable completely you do the square root of both b^2 and 144 which leaves you with the answer b=12. The leg is 12cm long.