Solve for X in 5x × 3 = 45: Basic Linear Equation

Because order of operations says multiplication happens before we solve for x! The equation $5x \cdot 3$ means $(5x) \times 3 = 15x$, so we need to divide by 15 to isolate x.

Yes! Division is the inverse of multiplication, so you can divide by 5 first to get $3x = 9$, then divide by 3 to get $x = 3$. Both methods work!

Check your work! Substitute back: $5(9) \times 3 = 45 \times 3 = 135 \neq 45$. When your check doesn't work, you know to look for the error.

Exactly! The equation $5x \cdot 3 = 45$ simplifies to $15x = 45$. Both forms give you $x = 3$ when you divide by 15.

Think of it like this: $5x \cdot 3$ means "5 times x, then multiply that whole thing by 3." So you're really multiplying x by $5 \times 3 = 15$!