Using the distributive property, 7(x + y) = 7x + 7y.
Multiply: 4(5a - 2b).
Distribute 4 over (5a - 2b) to find that 4(5a - 2b) = 20a - 8b.
Remember how exponent notation works? If not, get a refresher here. If we distribute something that has a variable over a quantity in parentheses that also contains that variable, we use exponent notation to keep things tidy. Probably couldn't hurt to also spray it down with a few squirts of Glass Plus.
Multiply: 3x(x + 2).
Now the thing we are distributing is 3x, rather than a plain old number all by its lonesome. That's okay, because the distributive property still works: 3x(x + 2) = 3x · x + 6x = 3x2 + 6x.
Distribute - 2(a + b).
- 2(a + b) = - 2a - 2b.
Be careful: When the value you are distributing has a negative sign, make sure you distribute the negative sign over everything in the parentheses. Your parents may need told you to stop spreading your negativity, but ignore them for now.