Your answer is B. 2
This is because to rationalise the denominator, we need to multiply it by (3 - √7), so we get:
(3 + √7)(3 - √7)
3 × 3 = 9
3 × √7 = 3√7
3 × -√7 = -3√7
√7 × -√7 = -7
So all in all you get 9 - 7 which is 2.
I hope this helps!
Width = x
length = x+10
Area of deck = 144 square feet
Area = length * width
144 = x(x+10)
Solving for x in a quadratic:
x²+10x = 144
x²+10x-144 = 0
Factor:
(x+18)(x-8) = 0
Solving for x:
x = 8, x = -18
Dimensions cannot be negative, therefore x = 8, only.
Length = x + 10
Length = 18
Width = 8
N-10+9n-3
n+9n=10n
10-3=7
so the answer is....
-13+10n
2.40/6 I believe tell me if it is right
