posted by mysterychicken .
Is it me or does this problem not make sense? (you can't solve it)
5. Solve for x in the following system:
6x + 6y = -2
y = -x
I also need help in these:
38. We can take the product AB only if the number of columns of A equals the number of rows of B. -True?
40. The graph of the following system yields perpendicular lines:
x + 2y = -10
-4y = 2x + 20
True or False?
42. If we multiply a 2 x 2 matrix with a 2 x 1 matrix, the product is a 2 x 1 matrix.