Answer: a) AB = ![\left[\begin{array}{ccc}-14&26\\-11&22\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-14%2626%5C%5C-11%2622%5Cend%7Barray%7D%5Cright%5D)
; b) ![\left[\begin{array}{ccc}5&-5\\13&9\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%26-5%5C%5C13%269%5Cend%7Barray%7D%5Cright%5D)
; c) No, they are different; d) No, they are never the same;
Step-by-step explanation:
a) A = ![\left[\begin{array}{ccc}-2&4\\1&3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%264%5C%5C1%263%5Cend%7Barray%7D%5Cright%5D)
, B = ![\left[\begin{array}{ccc}-2&1\\-3&7\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%261%5C%5C-3%267%5Cend%7Barray%7D%5Cright%5D)
. This multiplication is possible, because matrix A has 2 columns and matrix B has 2 rows. When those value are equal, the multiplication is possible.
AB = . =
b) BA = . =
c) As, we can see, parts a and b are differents.
d) With matrices, multiplication is not commutative, which means AB≠BA
So here, the rule "keep,change,switch" works great. so you keep the first fraction the same, switch the division to multiplication and then turn the second fraction upside down
so it looks like this:
-1 * -9= 9
7* 5= 35 = (9/35)
then
7* 9= 63 = (63/64)
8* 8= 64
All 3 angles of a triangle must equal to 180. You can simply set up an equation to solve this and set it equal to 180.
Angle 1 - 50 + x
Angle 2 - x
Angle 3 - 2x -10
50+x+x+2x-10=180
4x+40=180
4x=140
x=35
Angle 1 = 50+35= 85
Angle 2 = 35
Angle 3 = 2(35) - 10 = 60
60+35+85=180
