The value of k is -89
Explanation:
The given expression is 
We need to determine the output k, when the input t is -7
<u>Output k:</u>
The value of the output k can be determined by substituting the input
in the expression 
Thus, we have,

Multiplying the terms 10 and -7, we have,

Simplifying, we get,

Thus, the value of k is -89
The 3rd and 5th systems of equations are the answer.
Point A is at (3,-1), so all you do is input 3 for x and -1 for y into all the equations. For the systems to work, both equations must work with (3,-1).
Only the third and fifth boxes work.
Answer:
See solution below
Step-by-step explanation:
According to pythagoras theorem
hyp^2 = opp^2 + adj^2
10^2 = 4^2 + b^2
100 = 16 + b^2
b^2 = 100-16
b^2 = 84
b = √84
b ≈ 9
Using SOH CHA TOA identity
sin B = AC/AB
Sin B = 9/10
B = arcsin0.9
B ≈ 64degrees
sinA = BC/AB
Sin A = 4/10
A = arcsin0.4
A ≈ 24degrees
All you need to do is plug in the numbers and you'll get the sides.
A rational number is any number that can be expressed as a fraction
(ex: -5/2, 4 1/7, and 8/13)
An irrational number is any number that cannot be expressed as a fraction; a non-repeating, non-terminating decimal (ex: pi, 0.121231234...)
Hope this helps! :)