1, 3, 7, 21.
3*7 = 21
1 x 21, 3 x 7 = 21
They are: 25 minus 4 = 21
21 multiplies to 21 to make it 441
21 and 5
21+11 8x4
20 and 1
21 and 5
21*6=126
To find numbers that multiply to make -21, one number must be positive and the other must be negative. For example, 3 and -7 multiply together to give -21 (3 × -7 = -21). Other pairs include -3 and 7, or 1 and -21.
1, 2 and 21 when added.
3 and 7