x - 7 = 8
x = 7 + 8
x = 15
This is the product of 8 times 7. And that's 8 * 7 = 56, not 57.
I can prove that it's 56. 8 * 8 = 64, which is the number 8 eight times. So 8 * 7 = the number 8 but only seven times. One less 8 than the 64 problem. So 8 * 7 = 8 * (8 - 1) = 64 - 8 = 56 QED.
x+8=-4
If digits can't be repeated, then there are (7 x 7 x 6 x 5 x 4 x 3 x 2) = 35,280If digits can be repeated, then there are (7 x 8 x 8 x 8 x 8 x 8 x 8) = 1,835,008
short answer -1 and -7 long worked answer let x = one of the integers let y = the other integer x+y = -8 xy = 7 solve for y y = -8 - x plug y in x(-8 - x) = 7 rearrange -x^2 - 8x - 7 = 0 divide both sides by -1 x^2 + 8x + 7 = 0 factor (x + 7)(x + 1) = 0 x = -1, -7 y = -8 - x so y = -8 + 1 = -7 or -8 + 7 = -1 so when x = -1, y = -7 when x = -7, y = -1
-2 x -4 x -7 x -8 = 448
7 x 8 = 56
x - 7 = 8 x = 7 + 8 x = 15
The only common multiple of 7 and 8 up to 80 is 56. The multiples of 7 up to 80 are: 7 x 1 = 7 7 x 2 = 14 7 x 3 = 21 7 x 4 = 28 7 x 5 = 35 7 x 6 = 42 7 x 7 = 49 7 x 8 = 56 7 x 9 = 63 7 x 10 = 70 7 x 11 = 77 The multiples of 8 up to 80 are: 8 x 1 = 8 8 x 2 = 16 8 x 3 = 24 8 x 4 = 32 8 x 5 = 40 8 x 6 = 48 8 x 7 = 56 8 x 8 = 64 8 x 9 = 72 8 x 10 = 80
7 x 2 x 2 x 2
x+3/4 = 7/8 Is the same as: x+6/8 = 7/8 x = 7/8- 6/8 x = 1/8
-7 +2x = x + 8 2x - x = 7 + 8 x = 15
x+8=-4
7/8 x 8/9 = 7/9
If digits can't be repeated, then there are (7 x 7 x 6 x 5 x 4 x 3 x 2) = 35,280If digits can be repeated, then there are (7 x 8 x 8 x 8 x 8 x 8 x 8) = 1,835,008
X/8-4=7 X/8=11 X=11 x 8 X=88 ;-)
If √x + 8 = 7, then √x = -1, so x does not exist, because √ only refers to positive roots.If √(x + 8) = 7, then x + 8 = 49 and x + 41.
8(x - 7)
Double 4 x 7 to find 8 x 7.