## Introductory Algebra for College Students (7th Edition)

$84$
Substituting $8$ into $x$ and $10$ to $y$: $3(2y+x) \\=3(2\cdot 10 + 8)$ Simplify within the parentheses. Perform the multiplication first and addition next: $\\=3(20+8) \\=3(28)$ Multiply. $\\=84$