Answer:
486
Step-by-step explanation:
for the 2nd term, add 5 to -9
for the 3rd, add 5 × 2 to -9
for the 4th, add 5 × 3 to -9
:
for the 100th, add 5 × (100 - 1) to -9
=> 5 × 99 + (-9)
=> 486
Answer:
Step-by-step explanation:
Area = length * width
length: x + 3
width: x - 5
A = (x + 3)(x - 5)
Simplify (x + 3)(x - 5) using the FOIL method:
1. First numbers: multiply the first number of each binomial together--x*x = x%5E2
2. Outer numbers: multiply the outer number of each binomial (out of the entire expression, the number farthest to the left (x) and the number farthest to the right (-5))--x*-5 = -5x
3. Inner numbers: multiply the inner number of each binomial--3*x = 3x
4. Last numbers: multiply the last number of each binomial--3*-5 = -15
==> Now, add all of the results together and combine like terms: x%5E2+-+5x+%2B+3x+-+15 = x%5E2+-+2x+-+15
Therefore, A = x%5E2+-+2x+-+15
Answer:
x ∈ {-5, -1}
Step-by-step explanation:
Here's the solution using the quadratic formula:

The real zeros are -5 and -1.
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There are many ways to check your answer. One of them is to look at the given quadratic, which has no changes of sign in its coefficients. (They are all positive.) That means there can be no positive real roots, so already you know that x=0.5 won't work.
Also, the constant in the quadratic is the product of the roots, For your roots, their product is -7/4, so even multiplying by 4 (the leading coefficient in the given quadratic), you don't get anything like 20.
In tue picture, we can see 2 triangles and they already labeled 2 congruent sides. We also see that the line in the middle is being shared between the 2 triangles, making the side equal. Using the SSS theorem, we can prove that these teiangles are congruent to each other. Hope this helps.