It’s 90 degrees hope this helps
Answer:
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Step-by-step explanat ion :
Answer:
104 yd^2.
Step-by-step explanation:
Area of the 2 circles = 2 * π r^2
= 2 * π * 4^2
= 32 π yd^2.
Area of the side of the cylinder = 2 π r h
= 2 π * 4 * 9
= 72 π yd^2.
Total surface area = 32 + 72
= 104 yd^2.
Step-by-step explanation:
You can find the area of a right triangle the same as you would any other triangle by using the following formula:
A = (1/2)bh, where A is the area of the triangle, b is the length of the base and h is the height of the triangle; However, with a right triangle, it's much more convenient in finding its area if we utilize the lengths of the two legs (the two sides that are shorter than the longest side, the hypotenuse and that are perpendicular to each other and thus form the right angle of the right triangle), that is, since the two legs of a right triangle are perpendicular to each other, when we treat one leg as the base, then, consequently, we can automatically treat the length of the other leg as the height, and if we initially know the lengths of both legs, then we can then just plug this information directly into the area formula for a triangle to find the area A of the right triangle.
For example: Find the area of a right triangle whose legs have lengths of 3 in. and 4 in.
Make the 4 in. leg the base. Since the two legs of a right triangle are perpendicular to each other, then the length of the other leg is automatically the height of the triangle; therefore, plugging this information into the formula for the area of a triangle, we have:
A = (1/2)bh
= (1/2)(4 in.)(3 in.)
= (1/2)(12 in.²)
A = 6 in.² (note: in.² means square inches)
To solve these problems, we must remember the distributive property. This property states that a coefficient being multiplied by a polynomial in parentheses is equal to the sum of the coefficient times each of the separate terms. Using this knowledge, let's begin with number 21:
-(4x + 17) + 3(7-x)
To begin, we should distribute the negative sign through the first set of parentheses and the coefficient of positive 3 through the second set of parentheses.
-4x - 17 + 21 - 3x
Next, we must combine like terms, or add/subtract the constants terms and the variable terms in order to create a more concise expression.
-7x + 4 (your answer)
Now, we can move on to question 22 and solve it in a similar manner:
7(2n-8) - 4(12 - 8n)
Again, we will distribute the coefficients through the parentheses. However, keep in mind that the coefficient in front of the second set of parentheses is actually a NEGATIVE 4, so we must distribute the negative as well.
14n - 56 - 48 + 32n
Next, we will combine like terms (add the n terms together and subtract the constant terms).
46n - 104
Now, we can solve problem 23:
8 + 2(5f - 3)
We will again distribute through the parentheses:
8 + 10f - 6
Combine like terms after that:
10f + 2
Therefore, your answers for the three problems are as follows:
21) -7x + 4
22) 46n - 104
23) 10f + 2
Hope this helps!
