Answer:
C. T is not one-to-one because the standard matrix A has a free variable.
Step-by-step explanation:
Given

Required
Determine if it is linear or onto
Represent the above as a matrix.
![T(x_1,x_2,x_3) = \left[\begin{array}{ccc}1&-5&4\\0&1&-6\\0&0&0\end{array}\right] \left[\begin{array}{c}x_1&x_2&x_3\end{array}\right]](https://tex.z-dn.net/?f=T%28x_1%2Cx_2%2Cx_3%29%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%26-5%264%5C%5C0%261%26-6%5C%5C0%260%260%5Cend%7Barray%7D%5Cright%5D%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx_1%26x_2%26x_3%5Cend%7Barray%7D%5Cright%5D)
From the above matrix, we observe that the matrix does not have a pivot in every column.
This means that the column are not linearly independent, & it has a free variable and as such T is not one-on-one
Answer: number of adults = 3, number of children = 5
Step-by-step explanation:
let the number of adults be x, and the number of children be y.
x + y = 8 , 15x + 8y = 85
1st equation x 8 = 8x + 8y = 64

substitute x=3

7x - y= -5. Standard form is when it is written with x and y on the same side, but x is not negative or a fraction. To find the slope and y intercept, you must change the first two equations to slope intercept. You get y=7x-5 for the first one and y=11/3x+5 for the seccond equation. Take the 5 as your y intercept and the 7 as your slope and you get y=7x+5. Now you need to change it into standard form. When all is said and done, your final answer should be 7x - y = -5.
Because completementary angles add up to 180 degrees (angle 3 and angle 4)
and interior angles of a triangle will also add up to 180 degrees
if you compare these two facts, then angle 4 equals the 2 non adjacent interior angles