Well, in order to get that you had to do distributive property, distributive property is when you get the outside number next to the parenthesis and multiply it by the numbers or variable inside the parenthesis one by one. So if she was trying to explain how you got the answer you got then you would say you used the distributive property. Now the (-4x)2 would look like (-4x)(-4x) nad the (9)2 will look like (9)(9) that is why it results in 16x2+81. When you square something it means that you multiply the first number or variable or both times the same. That is why you got that answer. Now I am going to make clear that you r(-4x) changed from a negative to a postive because when you multiply a negative times a negative(or divide also) it results in a positve.
Hope I explained it enough
Answer:
Step-by-step explanation:
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Thanks
Answer:
5/6
Step-by-step explanation:
If the angle in B is 45º, that means the angle in A is also going to be 45º, considering it's a right triangle, so AC and BC are they have the same length.
Then using Pythagoras, you'll get that

equals

.
Now, you know that AC=BC and that AB=24.
So you'll get

. You do the square root in both sides and you get that 2AC=24 and AC=12.
Now that you know that both AC and BC equal 12, you can find the area by just multiplying them and then diving them by 2. (The formula for the area of a triangle is half base multiplied by height, and in a right triangle, if a cathetus is the base, the other cathetus<span> will be the height)
And so the area is equal to 72.</span>