Yes it is a square number
If we write y=f(x)=(x-h)²+k, then y-k=(x-h)². This is vertex form where the vertex is (h,k)=(3,3) so h and k are both 3. We can see this if we put x=3 in the shifted function. This is a minimum point for the function because for every other x f(x) is greater then 3. The minimum point is the vertex.
X = first number
x - 8 = 2nd number
5x = 3rd number
x + x - 8 + 5x = 69
7x - 8 = 69 <=== this is the equation u would use
7x - 8 = 69
7x = 69 + 8
7x = 77
x = 11
1st number = 11
2nd number : x - 8 = 11 - 8 = 3
3rd number : 5x = 5(11) = 55
Step-by-step explanation:
x²-y²=12
(x-y)(x+y)=12
but x-y=4
4(x+y)=12
x+y=12/4
x+y=3
lets make x the subject of the formula
x=3-y
since x-y=4
(3-y)-y=4
3-y-y=4
-2y=1
y=-1/2
then x=3-y
x=3-(-1/2)
x=(6--1)/2
x=7/2
therefore; x²+2xy+y
=(7/2)²+2×7/2×-1/2+(-1/2)
=49/4-7/2-1/2
=(49-14-2)/4
=33/4
=8.25
=8