How do you expand #(3x + 1) ( 5x + 7)#?

1 Answer
Jan 30, 2017

Answer:

See the entire solution process below:

Explanation:

To multiply these two terms you multiply each individual term in the left parenthesis by each individual term in the right parenthesis.

#(color(red)(3x) + color(red)(1))(color(blue)(5x) + color(blue)(7))# becomes:

#(color(red)(3x) xx color(blue)(5x)) + (color(red)(3x) xx color(blue)(7)) + (color(red)(1) xx color(blue)(5x)) + (color(red)(1) xx color(blue)(7))#

#15x^2 + 21x + 5x + 7#

We can now combine like terms:

#15x^2 + (21 + 5)x + 7#

#15x^2 + 26x + 7#