PLEASE HELP! HAVE NO IDEA! question in picture

  (x, y) = (-3, -5) or (1, 3)

Step-by-step explanation:

You can equate the expressions for y, then solve the resulting quadratic.

  -x^2 +4 = 2x +1

  4 = x^2 +2x +1 . . . . add x^2

  4 = (x +1)^2 . . . . . . . write as a square

  ±2 = x +1 . . . . . . . . . take the square root

  x = -1 ±2 = -3 or +1 . . . subtract 1

So, the solutions have x-values of -3 or +1. The corresponding y-values can be found from ...

  y = 2x +1

  y = 2(-3) +1 = -5   or   y = 2(1) +1 = 3

Solutions are ...

  (x, y) = (-3, -5) or (1, 3)

(n^3 - n)

= n(n-1)(n+1)

since it is divisible by 3 and 2 ,because it is a multiple 3 consecutive number

if, n-1 is odd then n+1 is also odd, then it is a multiple of 9

but if, n-1 is even then n+1 is also even, then it is a multiple of 4

so, largest multiple = max(9*2, 4*3) = max(18, 12) = 18

there are 70 more legs than eyes at the dog show (196 – 126 = 70). dogs have two more legs than eyes, and humans have the same number of legs as eyes. thus 70 is twice the number of dogs at the show, so the number of dogs is half of 70, which is 35. to get the number of humans, subtract 35 from 63: 63 – 35 = 28.

step-by-step explanation: