You make a check by they're name, then go to delete.
When multiplying exponential factors the exponents are added if bases are the same. 5^3 * 5^4 = 5^7 check it out on your calculator.
(3b - 1)(a - b)
(a - 2b)(c - 3d)
The expression, as given, cannot be factorised.
(2a + 3)(b - 3c)
There is no need to borrow when multiplying. You need to carry numbers when multiplying but not borrow.
Multiplying 6.7 and 5.5 is the same as multiplying 0.67 and 55, or 67 and 0.55.
multiplying. adding is permeter. sorry bout my spelling. not the best at it