Star Math algebra. Practice it free.

The constants $7$ and $2$ are like terms: $7 + 2 = 9$. The term $m^{2}$ stays the same, so the expression is equivalent to $m^{2} + 9\textsf{.}$

Distribute 2: $2 \cdot 4x + 2 \cdot -3 = 8x - 6$.

The equation means $3x - 12 = 24$ or $3x - 12 = -24$. Adding $12$ gives $3x = 36$ or $3x = -12$. Dividing by $3$ gives $x = 12$ or $x = -4$. Both solutions are $-4$ and $12\textsf{.}$

Rewrite $|6x + 12| = |6(x + 2)| = |6|\,|x + 2| = 6|x + 2|$. Since $6|x + 2| = 48$, divide by $6$ to get $|x + 2| = 8$. The expression $x + 2$ equals $8$ or $-8$; the positive value is $8\textsf{.}$

The greatest common factor of $20x^{2}$ and $30x$ is $10x\textsf{.}$ Factoring gives $10x(2x - 3)$.

At least $2$ gives $d \ge 2$. Less than $7$ gives $d < 7$, so $2 \le d < 7$.

The first number in an ordered pair is the $x$-coordinate. In $(4, 7)$ the $x$-coordinate is $4\textsf{.}$

$4x^{2} - 9 = (2x)^{2} - 3^{2} = (2x - 3)(2x + 3)$.