In order to use the remainder theorem, you need to have some idea what to divide by. The rational root theorem tells you rational roots will be from the list derived from the factors of the constant term, {±1, ±5}. When we compare coefficients of odd power terms to those of even power terms, we find their sums are equal, which means -1 is a root and (x +1) is a factor.
Dividing that from the cubic, we get a quotient of x² +6x +5 (and a remainder of zero). We recognize that 6 is the sum of the factors 1 and 5 of the constant term 5, so the factorization is
... = (x +1)(x +1)(x +5)
... = (x +1)²(x +5)
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The product of factors (x +a)(x +b) will be x² + (a+b)x + ab. That is, the factorization can be found by looking for factors of the constant term (ab) that add to give the coefficient of the linear term (a+b). The numbers found can be put directly into the binomial factors to make (x+a)(x+b).
When we have 1·5 = 5 and 1+5 = 6, we know the factorization of x²+6x+5 is (x+1)(x+5).
Answer:
y = - 
(x - 5)² + 7
Step-by-step explanation:
The equation of a quadratic in vertex form is
y = a(x - h)² + k
where (h, k ) are the coordinates of the vertex and a is a multiplier
Here (h, k ) = (5, 7 ) , then
y = a(x - 5)² + 7
To find a substitute (10, - 3 ) into the equation
- 3 = a(10 - 5)² + 7 ( subtract 7 from both sides )
- 10 = 5²a = 25a ( divide both sides by 25 )
= a , that is
a = -
y = - (x - 5)² + 7 ← in vertex form
Let's look at an example.
We'll add the fractions 1/6 and 1/8
Before we can add, the denominators must be the same.
To get the denominators to be the same, we can...
- multiply top and bottom of 1/6 by 8 to get 8/48
- multiply top and bottom of 1/8 by 6 to get 6/48
At this point, both fractions involve the denominator 48. We can add the fractions like so
8/48 + 6/48 = (8+6)/48 = 14/48
Add the numerators while keeping the denominator the same the entire time.
The last step is to reduce if possible. In this case, we can reduce. This is because 14 and 48 have the factor 2 in common. Divide each part by 2.
The fraction 14/48 reduces to 7/24
Overall, 1/6 + 1/8 = 7/24
