Express x^2+4x-7 in the form (x+a)^2-b where a and b are integers

Mathematics

1 answer:

lukranit [14]3 years ago

4 0

Answer:

(x + 2)^2 - 11.

Step-by-step explanation:

f(x) = x^2 + 4x - 7

Now x^2 + 4x = (x + 2)^2 - 4 so we have:

f(x) = (x + 2)^2 - 4 - 7

f(x) = (x + 2)^2 - 11.

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Find the coordinates of the vertices of each figure after the given transformation.

antiseptic1488 [7]

Answer: 9

Step-by-step explanation: process of elimination

7 0

3 years ago

Which of the following could be the equation for a parabola that opens down with the vertex (-11,-28)?

Mekhanik [1.2K]

Answer:y=-5(x+11)^2 -28

Step-by-step explanation: Okay think about what you know about translations and transformations of parent functions. In this case, the parent function is x2. So what now?

First, the problem states that the parabola opens DOWN. This means that you should look for a negative leading coefficient. This narrows your options down to C or D. (-5 is the leading coefficient)

Now starting with the x2, the vertex would be at (0,0), but in this problem it is at (-11,-28). That means it was TRANSLATED 11 spots in the negative x-direction and 28 spots in the negative y-direction.

Look at your options, when a number is being added directly unto the x variable, such as in answer C, it moves in the negative x-direction. This tells you that C has to be your answer.

I hope that helps!

8 0

3 years ago

Nina purchased apples and strawberries. She purchased a total of 9 pounds of fruit and spent a total of $16.35. Strawberries cos

irina [24]

Answer:

4 pounds of strawberries and 5 pounds of apples are bought.

Step-by-step explanation:

Given:

Total number of pounds of fruit = 9 pounds

Total money spent = $16.35

Cost of 1 pound of strawberry = $1.60

Cost of 1 pound of apple = $1.99

Let 'x' pounds of strawberries and 'y' pounds of apples are bought.

So, as per question:

The sum of the pounds is 9. So,

$x+y=9\\\\y=9-x----1$

Now, total sum of the fruits is equal to the sum of 'x' pounds of strawberries and 'y' pounds of apples. So,

$1.60x+1.99y=16.35----2$

Now, plug in the 'y' value from equation (1) in to equation (2). This gives,

$1.60x+1.99(9-x)=16.35\\\\1.60x+17.91-1.99x=16.35\\\\Combining\ like\ terms, we get:\\\\1.60x-1.99x=16.35-17.91\\\\-0.39x=-1.56\\\\x=\frac{-1.56}{-0.39}=4\ pounds$