Answer :
To simplify the expression
[tex]$$12x^2 + 9x^2,$$[/tex]
we notice that the terms are like terms because they have the same variable raised to the same power ([tex]$x^2$[/tex]). This means we can add their coefficients together.
Step 1: Identify the coefficients of the like terms. The coefficients are 12 and 9.
Step 2: Add the coefficients:
[tex]$$12 + 9 = 21.$$[/tex]
Step 3: Multiply the sum by the common variable factor:
[tex]$$12x^2 + 9x^2 = 21x^2.$$[/tex]
Thus, the simplified expression is
[tex]$$21x^2.$$[/tex]
The correct answer is A. [tex]$21x^2$[/tex].
[tex]$$12x^2 + 9x^2,$$[/tex]
we notice that the terms are like terms because they have the same variable raised to the same power ([tex]$x^2$[/tex]). This means we can add their coefficients together.
Step 1: Identify the coefficients of the like terms. The coefficients are 12 and 9.
Step 2: Add the coefficients:
[tex]$$12 + 9 = 21.$$[/tex]
Step 3: Multiply the sum by the common variable factor:
[tex]$$12x^2 + 9x^2 = 21x^2.$$[/tex]
Thus, the simplified expression is
[tex]$$21x^2.$$[/tex]
The correct answer is A. [tex]$21x^2$[/tex].
