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Row 1 column 2(a12)=-10
Hence,-10 is your answer.
Answer:
B. 
Step-by-step explanation:
5÷7 is also 
--that divided sign is what the fractional bar represents in a fraction.
now multiply 
both are the same result, so your answer is Choice B.
Let cheese wafers = x
chocolate wafers = y
we know they bought 20 total packets so x+y = 20, this can be re-written as x = 20-y
cheese wafers cost 2, so we have 2x
chocolate wafers cost 1, so we have 1y, which is just the letter y
so we know 2x + y = $25
replace x with x=20-y to get:
2(20-y)+y = 25
distribute the parenthesis:
40-2y +y = 25
combine like to terms to get:
40-y = 25
subtract 40 from each side"
-y = -15
divide both sides by -1
y = 15
chocolate wafers was y so they bought 15 chocolate wafers
cheese wafers was x, so they bought 20-15 = 5 cheese wafers
using the substitution method was the easiest way to isolate one of the variables in order to find the solution.
Answer:
Part A: chosen method is by factoring
Part B: First rewrite the equation by writing -24 as a difference so you get x² -9x - 15x + 135 = 0. Then factor out the x and the -15 from the equation so you get x(x-9) - 15(x-9) = 0. Then factor out x-9 from the equation so you have (x-9)(x-15) = 0. Finally, set each expression to 0: x-9=0 and x-15=0 and then solve: x=9 and x=15
Part C: x=9, x=15
Answer:
15x^2 - 12x^3
Step-by-step explanation:
A rectangular block has 3 parts that play into its volume. length, width and height. The question gives us length and width in the form of x and 3x, so height is what's missing.
It gives us a bit more information saying the sum of its edges is 20. We also have to ask how many lengths, widths and heights are there. That may be a bit hard to understand, but is you are looking at a block I could ask how many edges are vertical, just going up and down. These would be the heights. There are 4 total, and this goes the same for length and width, so 4*length + 4*width and 4*height = 20.
Taking that and plugging in x for length and 3x for width (or you could do it the other way around, it doesn't matter, you get:
4*x + 4*3x + 4*height = 20
4x + 12x + 4h = 20
16x + 4h = 20
4h = 20 - 16x
h = 5 - 4x
Now we have h in terms of x, which lets us easily find the volume just knowing x. To find the volume of a rectangular block you just multiply the length, width and height.
x*3x*(5-4x)
3x^2(5-4x)
15x^2 - 12x^3
Question doesn't give a specific value for x at all so you should be done there. Any number you plug in for x should get you the right answer
