Step-by-step explanation:
Here, we'll need to multiply these two values together. I'll use the expansion formula, which goes as follows:
[tex](a+b)(c+d)[/tex]
[tex]ac + ad + bc + bd[/tex]
Lets apply this to the following equation:
[tex](x+3) (x+7)[/tex]
[tex](x*x) + (x * 7) + (3 * x) + (3 * 7)[/tex]
[tex](x^2) + (7x) + (3x) + (21)[/tex]
[tex]x^2+10x+21[/tex]
Answer:
x^2+10x+21