tolong bantu ya teman2, pakek cara juga.. makasih..

Transformasi Geometri
Kelas XII
(Kita tes titik A)
[tex] \left[\begin{array}{cc}x' \\ y' \end{array}\right] =\left[\begin{array}{cc}2 & 1 \\ -1 & -3 \end{array}\right] \left[\begin{array}{cc}a & a + 1 \\ 1 & -2 \end{array}\right] \left[\begin{array}{cc}x \\ y \end{array}\right] \\ \left[\begin{array}{cc}22\\ -1 \end{array}\right] = \left[\begin{array}{cc}2a + 1& 2a \\ -a - 3& -a + 5 \end{array}\right] \left[\begin{array}{cc}2 \\ 3 \end{array}\right] \\ \left[\begin{array}{cc}22\\ -1 \end{array}\right] = \left[\begin{array}{cc}10a + 2\\ -5a + 9 \end{array}\right] Didapat \ 22 = 10a + 2 \ ->\ a = 2 \\ Matriks \ Transformasinya \ -> \left[\begin{array}{cc}2(2) + 1& 2(2) \\ -2 - 3& -2 + 5 \end{array}\right] \\ -> \left[\begin{array}{cc}5 & 4 \\ -5 & 3 \end{array}\right] \\ sehingga \left[\begin{array}{cc}70 \\ 35 \end{array}\right] = \left[\begin{array}{cc}5 & 4 \\ -5 & 3 \end{array}\right] \left[\begin{array}{cc}x \\ y \end{array}\right] \\ \left[\begin{array}{cc}70 \\ 35 \end{array}\right] = \left[\begin{array}{cc}5x + 4y \\ -5x+ 3y\end{array}\right] [/tex]

Eliminasi
5x + 4y = 70
-5x + 3y = 35
____________ (+)

7y = 105
y = 15

5x + 4(15) = 70
5x = 10
x = 2

Jadi C : (2 ,15)