23 x 10,000 = 230,000
Another name for 23 ten thousand is: Two hundred thirty thousand
And another name also is: 230 Thousands
Answer:B: 36°
Step-by-step explanation:
We know that ∆ABC is isoceles, making (angle)<ABC and <BCA congruent because base angles of isoceles triangles are congruent.
Because we have parallel lines, we can look for alternate interior angle pairs. <BCA is congruent to <DAC because they're alternate interior angles.
If <BCA is x then so is <ABC.
Since triangles add up to 180° we can add all of the angles (3x+x+x) and set it equal to 180.
3x+x+x=180
5x=180
x=36
If we were looking for <BAC we would plug that back in and solve, but we're looking for <BCA which is equal to x, therefore m<BCA=36°
Step 1: Trying to factor as a Difference of Squares:
Factoring: x²⁰⁰² - 1
Theory : A difference of two perfect squares, A² - B² can be factored into (A+B) • (A-B)
Proof : (A+B) • (A-B) =
A² - AB + BA - B² =
A² - AB + AB - B²
A² - B²
Note : AB = BA is the commutative property of multiplication.
Note : - AB + AB equals zero and is therefore eliminated from the expression.
Check : 1 is the square of 1
Check: x²⁰⁰² is the square of x¹⁰⁰¹
Factorization is : (x¹⁰⁰¹ + 1) × (x¹⁰⁰¹ - 1)
Answer: Choice C) 124 square cm
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Explanation:
Let's calculate the area of the trapezoid shown
b1 and b2 are the parallel bases; h is the height of the 2D trapezoid
b1 = 2
b2 = 5
h = 1.5
A = h*(b1+b2)/2
A = 1.5*(2+5)/2
A = 1.5*7/2
A = 10.5/2
A = 5.25
The area of one 2D trapezoid is 5.25 sq cm
There are two of these trapezoids that form the base faces of the trapezoidal prism. So the total base area is 2*5.25 = 10.5 sq cm
Keep this value (10.5) in mind. We'll use it later.
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Now onto the lateral surface area (LSA)
It turns out that the formula for the LSA is
LSA = p*d
where
p = perimeter of the trapezoid shown
d = depth or height of the 3D trapezoid (I'm not using h as it was used earlier)
This formula works for any polygonal base. It doesn't have to be a trapezoid.
In this case the perimeter is,
p = 1.7+2+2.65+5
p = 11.35
So
LSA = p*d
LSA = 11.35*10
LSA = 113.5
Add this LSA to the base area found earlier
10.5+113.5 = 124
The total surface area is 124 square cm
