Answer:
√27
Step-by-step explanation:
The triangles of the pyramid are equilateral triangles with sides of 6''.
Dividing a triangle into two equal parts we get two congruent right triangles, with a hypotenuse of 6'', one leg of 3'', and the other leg is the slant height (s). From Pythagorean theorem:
3² + s² = 6²
s² = 6² - 3²
s = √27
If we let Q be the number of quarters and N be number of nickels, this is the formula we would use:
[1] 25Q + 5N = 635 (using cents instead of dollars)
We also know something about Q and N.
[2] Q + N = 51
So multiply both sides of the second equation by 5. The reason we do this is because we're going to need to cancel out one of the variables (either Q or N) to solve for the other one. If we multiply times 5, we'll have 5N in both equations.
5Q + 5N = 255
Now we have two equations, and the second one can be subtracted from the first.
25Q + 5N = 635
-(5Q + 5N) = -255
---------------------
20Q = 380
so
Q = 19
There are 19 quarters.
And since there are 51 coins in all, 51-19 = 32 nickels.
Answer:
A. 15
Step-by-step explanation:
Ooh, look! This triangle is a Pythagorean triple! Without even needing to use a formula, I can tell that you are correct and the answer is A. 15.
It's based off of a 3-4-5 right triangle, because 9-12-15 simplifies to that if you divide every term by 3. It's basically just a bigger version of a 3-4-5 triangle! Isn't math cool:)
Answer: C.36
Step-by-step explanation:
90 ones would make 9 tens. It makes 9 tens because theres a 0 after 90. The 0 represents another place value. You can write this as 9 groups of ten