Answer:
The first one is -2x^2 - 21x + 4, the second one is -15 (I think, not 100% sure), the third one is 4xyz + 3yz + 5x - 4 (also not 100% on this one)
Answer:
Multiply the first fraction by 
Multiply the second fraction by 
Step-by-step explanation:
Given

Required
Make the denominator equal

Factorize the denominator


Multiply the first fraction by 
Multiply the second fraction by 



<em>The expression now have the same denominator</em>
Answer:
B. 3(2^x)
Step-by-step explanation:
3(2^x) is the only function that yielded the given outputs when the inputs were plugged in.
Answer:
x=-2, y=3. (-2, 3).
Step-by-step explanation:
y=-x+1
y=3
----------
-x+1=3
-x=3-1
-x=2
x=-2
y=-(-2)+1
y=2+1=3
Answer:

Step-by-step explanation:
We know that:
- The initial conditions are -7 meters at 0 minutes.
- Then, after 6 minutes, he was 16 meters below the ground.
According to these two simple facts we can found the linear function that describes this problem. First, the problem says that Mr. Mole is descending at a constant rate, which is the slope of the function. Now, to calculate the slope we need to points, which are
and
, where <em>t-values </em>are minutes, and <em>y-values </em>are meters. You can see, that the first point is the initial condition and the second point is 6 minutes later.
So, we calculate the slope:

From the slope we can see that Mr. Mole is descending, because it has a negative sign. Also, the point
is on the <em>y-axis</em>, because <em>t</em> is null, so -7 is part of the function. Therefore the function that describes this problem is:
