
1) Let's evaluate that expression, given that a=4.9, b=-7, and c=-0.5

Note that we have rewritten it as a fraction so that we can easily operate. Also, we have applied here the PEMDAS order of operations, prioritizing the exponents.
Answer:
y = -5
Step-by-step explanation:
see the pic for the steps . .
40.5
Trust me i did it and got it right!! if its wrong lmk and i can explain it for u
When you are looking for a unit rate in a graph you want to know how much the dependent (y) variable will increase by when the independent (x) variable is increased by one
Answer:
Bobby around 131 minutes and Billy around 111 minutes
Step-by-step explanation:
To solve the problem it is important to raise equations regarding what happens.
They tell us that Billy (Bi) and Bobby (Bo) can mow the lawn in 60 minutes. That is to say that what they prune in a minute is giving as follows:
1 / Bo + 1 / Bi = 1/60 (1)
They say Billy could mow the lawn only in 20 minutes less than it would take Bobby, therefore
1 / Bi = 1 / (Bo-20) (2)
Replacing (2) in (1) we have:
1 / Bo + 1 / (Bo-20) = 1/60
Resolving
(Bo - 20 + B0) / (Bo * (Bo-20) = 1/60
120 * Bo - 1200 = Bo ^ 2 - 20Bo
Rearranging:
Bo ^ 2 - 140Bo -1200 = 0
Now applying the general equation
Bo = 130.82 or Bo = 9.17, <em>this last value cannot be because Billy took 20 minutes less and neither can he prune faster than the two together</em>, therefore Bobby only takes around 131 minutes and Billy around 111 minutes
Checking with equation 1:
1/131 +1/111 = ~ 1/60