Try it with some random number, like a=3.
Is "3+0 = 0+3 = 0" true? No.
If you were doing multiplication, then it would be true, but not with addition.
Answer:
D - (D/5)
Step-by-step explanation:
Let's imagine that D equals 100 dollars -
Well, we know that to get 20% of an amount, we need to divide the amount by five. So let's do that -
100 / 5 = 20
We now know that 20% of 100 dollars is equal to 20 dollars. We have now finished the first part. On to the second part.
We now need to take away 20% of 100 dollars off of 100 dollars - this is the price of the item after the discount.
100 - 20 = 80 dollars.
We now fit in D instead of 100 dollars -
D - (D/5)
X = height of pole (in meters)
With respect to the 50 degree angle, the side x is the opposite leg. It is the leg furthest from the reference angle. The hypotenuse is 5 meters.
The trig function sine ties together the opposite and hypotenuse
sin(angle) = opposite/hypotenuse
sin(50) = x/5
5*sin(50) = x .... multiply both sides by 5
x = 5*sin(50)
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Since x = 5*sin(50) isn't listed as an answer choice, let's try using cosine. We can't use it right away because we don't know the adjacent side. What we can do is change the reference angle. The missing angle of the triangle is 90-50 = 40 degrees. Let's make the 40 degree angle the reference angle
So x is now the adjacent side with respect to the 40 degree reference angle. The hypotenuse is always the longest side. The hypotenuse stays at 5.
cos(angle) = adjacent/hypotenuse
cos(40) = x/5
5*cos(40) = x
x = 5*cos(40)
This expression is listed. The answer is choice B
That would be 8, its in the center so forget 9 or 7.
