Assuming that the cost per minute is the same for both months and the plan fee is the same, you can use y=mx+b for this
y is the cost of the phone plan, x is the cost per minute and b is the start cost.
so 19.41=25x+b for the first month
and 45.65=380x+b for the second month
solve both for b you get:
19.41-25x=b and 45.65-380x=b. from this we get
19.41-25x=45.65-380x
solve for x
328x=26.24 and x=0.08
this means the cost per minute is 0.08c/min (answer A)
rewrite the equation to calculate b, and where this time, the x is the number of minutes talked.
y=0.08x+b and plug in one of the two months
45.65=0.08 * 380 + b
Solve for b and b is 15.25
so the final equation is
y=0.08x+15.25 (answer B)
Answer:
X= -0.1290 (bar line on top of the 90)
Hope this helps!
Step-by-step explanation:
Its letter D
7(19)-21 (x=19)
133-21=112 (RZ)
112+112=224 (RT)
Answer:
5 + 8 + 11 + 10 = 34
Step-by-step explanation:
The lengths of the horizontal and vertical sides are easily determined. The slant side is seen to be the hypotenuse of a 3-4-5 triangle (times 2), so is 10 units long. The perimeter is the sum of the side lengths:
5 + 8 + 11 + 10 = 34
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You can always estimate the length of the hypotenuse of a right triangle as being between 1 and 1.5 times the length of the <em>longest</em> side. Here, the longest side of the right triangle whose hypotenuse is of interest is 8 units, so the hypotenuse will be between 8 and 12 units long. That means the perimeter of the blue trapezoid will be between 32 and 36, a guess of sufficient accuracy to allow you to choose the correct answer.
In a figure like this, you can also measure the hypotenuse on the grid. Using a compass, ruler, or a piece of paper with a couple of marks, you can rotate the slant length so that it corresponds to a vertical or horizontal grid line. Then the length of it is easily estimated to good accuracy. (See the second attachment.) As we said in the previous paragraph, even poor accuracy is sufficient to choose the correct answer.
Answer: in decimal form its -2.17
exact form is -37/17
and mixed number form its -2 3/17