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I need help answering some of my daughter's math problems... please phrase the answers so I can help her as though I know what I am talking about...
7+3t/4 = -t/8
Hi Duncan,
The use of brackets is really important, as it can change the mathematical syntax completely.
Your question may be interpreted in two ways.
If it reads 7+(3/4)*t = -t/8, i.e., the second term is "three-quarters of t", then, it is solved like this.
The idea is to separate the knowns (numbers) from the unknowns (we have just one variable, "t", here in this question).
7+(3/4)*t = -t/8 ...separate the t's onto one side of the equation, we do this by subtracting both sides by (3/4)*t
7 = -t/8 -(3/4)*t ...next, factorize the RHS
7 = -(1/8 + 3/4)*t ...simplify the fraction
7 = -(1/8 + 6/8)*t
-7 = (7/8)*t ...divide throughout by 7/8 OR multiply throughout by the inverse 8/7.
-7*(8/7) = (8/7)*(7/8)*t ...cancel common factors
t = -8
On the other hand, if the question reads (7+3t)/4 = -t/8, the first step is to multiply both sides by 8.
We get 2*(7+3t) = -t
14+6t = -t
14 = -7t
t=-2.
cheers.
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| Rating(1-10) | Knowledgeability = 10 | Clarity of Response = 10 | Politeness = 10 |
| Comment | I am sorry about the low rating for the response time, but in this day and age, everything is instant or nearly... three days is a long waiting period. However, the answer was clear, concise and correct...and I was provided with an alternative answer because I did not phrase the original question clearly enough. Excellent job, Josh. Thank you. | ||
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Josh
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When I work through problems, I like to emphasize concepts which I believe are worth noting. I will try to answer questions in the following areas, but not at the advanced level. Algebra. Sequences & Series. Trigonometry. Functions & Graphs. Coordinate Geometry. Quadratic Polynomials. Exponential & Logarithms. Basic Calculus. Probability, Permutation and Combination. Mathematical Induction. Complex numbers. Physics problems.
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I have worked as a teaching assistant in college. My hope is that more people will share knowledge without boundary, give help without seeking recognition or monetary rewards.
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Bachelor degree in Engineering Science
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