Answer:
16x² − 56x + 49
Step-by-step explanation:
The square of difference of two terms can be expressed as a perfect square trinomial in the following manner:
![(a-b)^{2}=a^{2}-2ab+b^{2}](https://tex.z-dn.net/?f=%28a-b%29%5E%7B2%7D%3Da%5E%7B2%7D-2ab%2Bb%5E%7B2%7D)
The symbol with square terms must be always positive. So this removes the first two options from the given choices. The correct option is either c or d.
Only the option d can be expressed as a perfect square as shown below:
![16x^{2}-56x+49\\\\ = (4x)^{2}-2(4x)(7)+(7)^{2}\\\\ =(4x - 7)^{2}](https://tex.z-dn.net/?f=16x%5E%7B2%7D-56x%2B49%5C%5C%5C%5C%20%3D%20%284x%29%5E%7B2%7D-2%284x%29%287%29%2B%287%29%5E%7B2%7D%5C%5C%5C%5C%20%3D%284x%20-%207%29%5E%7B2%7D)
Option c would have been correct if it was -30b instead of -15b i.e. the middle term is twice the product of first and second term.
So, option D is correct
Y= x²- 6x +7
Vertex form is y= a(x-h)² +k
The vertex form of this equation would be y= (x-3)²- 2 because if we transform to the standard form it would be equal to y= x²-6x+7 so we just have to complete the perfect square (which means to complete, following the rules, with the numbers that will make this equation right in the standard form).
How our x² is equal to 1 on our standard form (like it is not 2x², it is just x²), our ''a'' on the vertex form is 1 so we simply don't have to write the 1 in front of it so it stays y= 1(x-3)² -2 or y=(x-3)²-2. Look how it works: (x-3)² we use the rule of a²+2ab+c² which is the square of the first x² plus two times the first term times the second -6x plus the square of the last term (-3)² = 9 so we have x²-6x+9 - 2 that gives us the standard form x²-6x+7. So, that's true that the vertex form is y=(x-3)²-2
Answer:
So if he needs 1.5 of the lemonade mix, to find how much you need, simplu divide.
Step-by-step explanation:
4.5/1.5=3
He can make 3.
Answer: Rafdeal has 9 sessions in 3 days.
Step-by-step explanation:
Given: Time spent on daily practice =
hour
Duration of each session =
hour
Number of sessions in a day = ![\dfrac34\div\dfrac14= 3](https://tex.z-dn.net/?f=%5Cdfrac34%5Cdiv%5Cdfrac14%3D%203)
The number of practice sessions Rafdeal has in 3 days = 3 x (Number of sessions in a day ) = 3 x 3 =9
Hence, the number of practice sessions Rafdeal has in 3 days = 9
Answer:
The answer is 12x+6y-24
Step-by-step explanation: