Factor and set each factor equal to zero:
x = -3, 3, 2i, -2i
For this question, it would be most effective to use an algebraic expression to more easily show what the question is asking. If we use the variable "k" to show the distance in km that he cycled on Sunday, we know that the amount he cycled on Saturday equals k + 12, and the amount that he cycled on the weekend should be the amount of Saturday plus the amount of Sunday. If we write this as an equation we say:
k + k + 12 = 38
=> 2k + 12 = 38
Now we can just rearrange and solve for k:
=> 2k = 26
=> k = 26/2 = 13
Therefore Patrick cycled 13km on Sunday
To solve the answer, we just add 12km to the value for Sunday like so:
12 + 13 = the amount he cycled on Sunday
Hope this helped, remember to please try and understand the maths as well as the answer :))
Answer:
The other rational number is
.
Step-by-step explanation:
First rational number is ![\dfrac{-2}{3}](https://tex.z-dn.net/?f=%5Cdfrac%7B-2%7D%7B3%7D)
Let other rational number is ![\dfrac{x}{y}](https://tex.z-dn.net/?f=%5Cdfrac%7Bx%7D%7By%7D)
The product of two rational numbers is ![\dfrac{-28}{81}](https://tex.z-dn.net/?f=%5Cdfrac%7B-28%7D%7B81%7D)
According to question,
![\dfrac{x}{y}\times \dfrac{-2}{3}=\dfrac{-28}{81}](https://tex.z-dn.net/?f=%5Cdfrac%7Bx%7D%7By%7D%5Ctimes%20%5Cdfrac%7B-2%7D%7B3%7D%3D%5Cdfrac%7B-28%7D%7B81%7D)
Multiplying both sides by (-3/2) such that,
![\dfrac{x}{y}\times \dfrac{-2}{3}\times \dfrac{-3}{2}=\dfrac{-28}{81}\times \dfrac{-3}{2}\\\\\dfrac{x}{y}=\dfrac{14}{27}](https://tex.z-dn.net/?f=%5Cdfrac%7Bx%7D%7By%7D%5Ctimes%20%5Cdfrac%7B-2%7D%7B3%7D%5Ctimes%20%5Cdfrac%7B-3%7D%7B2%7D%3D%5Cdfrac%7B-28%7D%7B81%7D%5Ctimes%20%5Cdfrac%7B-3%7D%7B2%7D%5C%5C%5C%5C%5Cdfrac%7Bx%7D%7By%7D%3D%5Cdfrac%7B14%7D%7B27%7D)
So, the other rational number is
.
It has a minimum value at x = 3 and f(x) = 4
Vertex form is
f(x) = a(x - 3)^2 + 4 where a is some constant to be found
From the graph when x = 5 f(x) = 15, so
15 = a * 2^2 + 4
a = 15-4/4 = 11/4
so our equation is f(x) = 11/4(x - 3)^2 + 4
You can set up this equation as:
![x = 0.7(120)](https://tex.z-dn.net/?f=x%20%3D%200.7%28120%29)
Because remember, 70% is equal to 0.7 and x represents the unknown value. So, let's just solve it:
![x = 0.7(120)=84](https://tex.z-dn.net/?f=x%20%3D%200.7%28120%29%3D84)
So,
70% of 120 is 84.