\[ \text { lika } P=\left(\begin{array}{ll}1 & 2 \\ 1 & 3\end{array}\right) \operatorname{dan}\left(\begin{array}{cc}x & y \\ -z & z\end{array}\right)=2 P^{-1} \text {, Dengan } P^{-1} \] menyatakan invers matriks \( P \), maka \( x+y=\ldots \)

tinh \( a x^{2}+2 x+3 y=6 \)

Roger was told to think of a number, add 20 , then divide the result by 3 . The answer was Jower than Roger's original number. Deteruine the range of possible numbers Roger may have originally chosen.

5.7 Determine the equation of \( h \) if \( h(x)=g(x+1)-2 \)

In the \( x y \)-plane, a parabola has vertex \( (9,-14) \) and intersects the \( x \)-axis at two points. If the equation of the parabola is written in the form \( y=a x^{2}+b x+c \) where \( a, b \), and \( c \) are constants, which of the following could be the value of \( a+b+c \) ? (A) -23 (B) -19 (D) -12

8. \( \frac{\sqrt{27 a^{3} b^{6}}}{\sqrt{3 a b^{6}}-5 a b^{2}}= \)