How do I expand 3x (2-10x)

6x - 30x²

Step-by-step explanation:

multiply each term in the parenthesis by the 3x outside

3x (2 - 10x)

= (3x * 2) + (3x * - 10x)

= 6x + ( - 30x²) = 6x - 30x²

(3x + 5) ^2 expands into two binomials: (3x + 5) (3x + 5)

from there, you foil them:

(3x + 5) (3x + 5)

multiply the first terms ... 9x^2

the inside terms ... 9x^2 + 15x

outside terms ... 9x^2 + 15x + 15x

last terms ... 9x^2 + 15x + 15x + 25

then add like terms ... 9x^2 + 30x + 25