1. (2r + 9)(2r-9) = 4r^2 -81
+ (2r - 9)^2 = 4r^2 - 36r + 81
= 8r^2 - 36r
2. 12 - 5 [ a^2 + a - 1 ] + 5a
= 12 - 5a^2 - 5a + 5 +5a
= 17 - 5a^2
x^3 + 3x^2 + 6x + 18
______
3. x-3/ x^4 + 7
- ( x^4 - 3x^3)
----------------
3x^3 + 7
- (3x^3 - 6x^2)
-------------------
6x^2 + 7
- (6x^2 - 18x)
-------------------
18x + 7
- (18x - 54)
--------------
7 + 54 = R = 61
welp That's What I get
It is 1966. Hope it helps!
Yes they can because the two smaller numbers add up to be more than the bigger number
248 divide by 8 = 31 so she gets 31$ for mowing 1 lawn