3(3x+3)=8x+5 Solve the equation above for x. Which of the following is correct?
A. 1
B. 4
C. -1
D. -4
We use the order of operation to solve for the unknown value of x.
3(3x+3)=8x+5
Multiply 3 with each number in the brackets
(3*3x)+(3*3)=8x+5
9x+9=8x+5
Subtract 9 from both sides
9x+9-9=8x+5-9
9x=8x-4
Subtract 8x on both sides
9x-8x=8x-8x-4
x=-4
Thus, the unknown value of x is -4.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Math
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Q #1: Which of the following is the weight of the cargo in a truck if 2/3 of the cargo weighs 530 pounds (lb)?
A. 795 lb
B. 1030 lb
C. 1590 lb
D. 688 lb
Answer Explanation
The truck carries a whole cargo which equals 1. If we let the weight of the cargo to be p, then we set up a proportion equation with weight as numerator and fraction of cargo as denominator.
Solve for value of p by cross products
Multiply both sides by 3/2 a reciprocal of 2/3
The truck carries a cargo weighing 795 lb.
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Q #2: A couple dining at a restaurant receives a bill for $58.60. They wish to leave a 16% gratuity. Which of the following is the estimated gratuity?
A. $8.48
B. $6.40
C. $9.38
D. $7.00
Answer Explanation
In this problem, we need to find the amount of gratuity the couple will leave. The gratuity is 16% of the total bill. Before solving the problem, the following are terms and their meaning in percent problems:
- Is means equals
- Of means multiply
- What means unknown (variable)
If we let x be the amount of gratuity, then translating the given problem into a mathematical equation becomes:
Now we evaluate the above equation noting that of means multiply.
So, the value of x=9.376 and to the nearest cent, x=9.38
There, a couple will leave a gratuity of $9.38.
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Q #3: One gallon of cleaning solution requires 10 oz of ammonia. If the maintenance department needs 51 gallons of solution to clean all of the floors, how much ammonia is needed?
A. 510 gallons
B. 51 gallons
C. 510 oz
D. 51 oz
Answer Explanation
We use given information to find how much ammonia is need to make the specified solution.
We are told, one gallon of cleaning solution requires 10 oz of ammonia. Expressing this mathematically yields two options:
\(\frac{10\ oz\ of\ ammonia}{1\ gallon\ of\ solution}\) or \(\frac{1\ gallon\ of\ solution}{10\ oz\ of\ ammonia}\)
Now we find how much ammonia is needed using option two.
\(51\ gallon\ of\ solution\ *\frac{10\ oz\ of\ ammonia}{1\ gallon\ of\ solution}\ =\ 510\ oz\ of\ ammonia\)
From the above equation, gallon of solution will cancel, and oz of ammonia is left.
Therefore, the solution will require 510 oz of ammonia.
