Answer:
The answer is A(-3,-4) B(-1,2) C(2,1) D(0,-5)
Step-by-step explanation:
Answer:
as written: 2500.2
as intended: 3000
Step-by-step explanation:
20% = 0.2, so adding 0.2 to 2500 gives 2500.2
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We suspect you want to add 20% of 2500 to 2500. That is ...
2500 + 20%×2500
= 2500 + 0.20×2500
= 2500 + 500
= 3000
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<em>Comment on percentages</em>
A percentage is a pure number. It is a ratio of like quantities, so has no units.* A <em>useful</em> percentage always has a base. That is, it is a percentage <em>of something</em>. Sometimes that base may be unclear or unstated, in which case the percentage might very well be considered to be meaningless.
In any event, a percentage is simply a (unitless) fraction. The "%" symbol means the same thing as "/100", so 20% means 20/100 = 2/10 = 1/5.
The very clear math expression 2500 +20% means simply 2500 + 1/5, which is the mixed number 2500 1/5 or the decimal value 2500.2. Usually, when we want to add a percentage to some value, we want the percentage to be <em>of the original value</em>. When that is written as a math expression, it must show this:
2500 + 20% of 2500
2500 + 20%×2500
2500(1 +20%)
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* The concentration or potency of some medicines or other mixtures may be expressed as a percentage that is the ratio of one unit to a different unit, typically weight per volume. That is, a "0.1%" preparation may be 0.1 grams per 100 mL, for example. You have to read the label to determine whether this is the case. Mathematically, this is not a percentage, but is a non-standard use of the "%" symbol to indicate a ratio to 100 of something.
Answer: choice B, 40.5 degrees
The triangle is isosceles based on the fact that AC = BC (the tick marks are the same). The angles opposite the congruent sides are also congruent
angle A = angle B = x for some unknown number x
The three angles A,B,C add to 180, so,
A+B+C = 180
x+x+99 = 180
2x+99 = 180
2x = 180-99
2x = 81
x = 81/2
x = 40.5
So angle A and angle B are both 40.5 degrees
Check:
A+B+C = 180
40.5+40.5+99 = 180
180 = 180 answer is confirmed
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Edit
The sides with the two tick marks are the same length, so 7x-4 is the same as length as 31
7x-4 = 31
7x = 31+4
7x = 35
x = 35/7
x = 5
Answer is choice B) 5