<em><u>Answer:</u></em>
4 or 7 (Check the explanation to see which one your equation <em>actually</em> is.
<em><u>Step-by-step explanation:</u></em>
One thing I want to clarify for you, It's Evaluate, not Avaluate.
Okay so, we want to find the value of 2^3x-1 and we know x = 1.
You didn't really clarify if the expression was
or
, so I'll be doing both:
For
, we should plug in x to get
and then simplify to get
.
2 to the power of 2 or
is equal to 2 * 2 or 4.
The second one,
, we should plug in x to get
and then to become
. 2 to the power of 3 or
is 8 and then minus 1 is 7.
Make them both improper fractions.
77/10 - 19/5
Give them common denominators (multiply the second fraction by 2)
77/10 - 38/10
Subtract
39/10 = 3 9/10
<u>Answer:</u>
x + y ≥ 26 + 15
5x + 8y ≥ 250 (see below)
Step-by-step explanation:
First, write an equation to represent the total cost to wash cars:
$5x = cost for cars
Then, write another for trucks:
$8y = cost for trucks
If the question is saying that they will wash at least 26 cars and 15 trucks, that means they could wash more. This means that we'll need an inequality:
This inequality represents that the total number of cars and trucks they wash will be at least—which means that it is equal to or greater than—than the amount given:
x + y ≥ 26 + 15
Any equation or inequality with two unknowns is not solvable, meaning we need a system of equations:
If they make at least $250, that means that we need to combine the costs of the cars and trucks to make an inequality:
5x + 8y ≥ 250
Now you have your system of equations:
x + y ≥ 26 + 15
5x + 8y ≥ 250