If 2 sodas and 4 hamburgers are $12.00 and 4 sodas and 2 hamburgers are $9.00 how much is a single hamburger?
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2s + 4h = 12, (1) 4s + 2h = 9. (2) Multiply (1) by 2. You will get 4s + 8h = 24, (1') 4s + 2h = 9. (2') Distract (2') from (1'). You will get 8h - 2h = 24 - 9, or 6h = 15 ---> h =  =  = 2.5. Thus one hamburger price is $2.50. Then from (1) s =  = 1. Answer. One hamburger price is $2.50 and 1 soda costs $1.00.
There is even more elegant way to solve the problem.
Simply add all hamburgers and all sodas. 6 hamburgers and 6 sodas. $12 + $9 = $21.
Hence, 1 hamburger + 1 soda =  = $3.50.
Having this, everybody can solve to the end in this way, actually, without equations and using the mental math only.
Question: A man measures the angle of elevation to the top of a mountain to be 12 degrees. He drives 7 miles closer and finds the angle of elevation to be 37 degrees. How high is the mountain?
Answer:
-9 and 6
Step-by-step explanation:
The answer is: " Four hundred three and six hundred three thousandths. "
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Answer:
15 sqrt a ^4
Step-by-step explanation:
Start by isolating the X.
1 :
x + 1 ¾ = 2 4/8
- 1 ¾ - 1 ¾
2 :
x = (2 4/8) - (1 ¾)
3 :
In order to subtract the fractions, you need to find a common denominator.
The common denominator can be found by multiplying the two denominators together.
4 x 8 = 32
4 :
Rewrite each fraction as an equivalent fraction with a denominator of 32.
4/8 —> (4 x 4)/(8 x 4) —> 16/32
¾ —> (3 x 8)/(4 x 8) —> 24/32
5 :
Subtract the numerators. Simplify the answer if needed.
16/32 - 24/32
16 - 24 = -8
-8/32 —> (-8/4)/(32/4) —> -2/4
-2/4 —> (-2/2)/(4/2) —> - ½
6 :
(2 - 1) - ½ —> 1 - ½ = ½
Final answer : X = ½ :)
