If 2 sodas and 4 hamburgers are $12.00 and 4 sodas and 2 hamburgers are $9.00 how much is a single hamburger?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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?
Step-by-step explanation:
x = one odd number
the second odd number is (x+2), as both are consecutive.
so,
x × (x + 2) = 195
x² + 2x = 195
x² + 2x - 195 = 0
the formula to solve this is
x = (-b ± sqrt(b² - 4ac))/(2a)
in our case
a = 1
b = 2
c = -195
x = (-2 ± sqrt(4 - 4×1×-195))/(2×1) =
= (-2 ± sqrt(4 + 4×195))/2 = (-2 ± sqrt(784))/2 =
= (-2 ± 28)/2 = -1 ± 14
x1 = -1 + 14 = 13
x2 = -1 - 14 = -15 which is invalid as the numbers are positive.
so, the two numbers are 13 and 15.
B)$20 but also dam these mother truckers are broke.
Answer:
i think 4 4 kilograms if im wrong sorry
Step-by-step explanation:
