Answer:
x = 15
Step-by-step explanation:
The easiest way to solve this is to realise that a triangle takes up half the area of a rectangle of the same width and height.
We are told that the width of the triangle is 10, and that the line of length 10 is perpendicular to the longest side of the triangle. Because of that we know that x can be multiplied by ten to get the area of the rectangle that is twice the area of the triangle.
We are also told that the triangle's area is 75 units. With all of that put together, we can say:

Answer:
The answer is A.
Go to desmos and type your equation in
This is a question of proportions:
First we can work out how many feet it goes up for each feet he steps back:
5.5/6 ft per each feet he steps back.
Now we can multiply this by the amount of ft back the cliff is:
(5.5/6)*30 = 27.5 ft
Thus the cliff is 27.5 ft tall,
Hope this helps :)
This sets up as a very commonly used proportion.
90 oz / 18.95 = 1 oz / x Cross multiply
90 x = 18.95 Divide by 90
x = 18.95 / 90
x = 0.21 dollars or 21 cents.
So each ounce of shampoo costs 0.21 dollars or 21 cents.
This is a very handy way to check best deals. Stores have trained us for years to believe that the more we buy of a brand, the better the price. It isn't always true. Sometimes buying the smaller quantity is the better deal. There is only one way to be sure and that's to do a proportion like this one.
Try this is an example. The same company makes a smaller container of shampoo of 45 oz for 9.15. How much is 1 oz and which is the better deal? You should get 0.20333 dollars so this is marginally (just) the better deal.