Answer:
(1, 3)
Step-by-step explanation:
You are given the h coordinate of the vertex as 1, but in order to find the k coordinate, you have to complete the square on the parabola. The first few steps are as follows. Set the parabola equal to 0 so you can solve for the vertex. Separate the x terms from the constant by moving the constant to the other side of the equals sign. The coefficient HAS to be a +1 (ours is a -2 so we have to factor it out). Let's start there. The first 2 steps result in this polynomial:
. Now we factor out the -2:
. Now we complete the square. This process is to take half the linear term, square it, and add it to both sides. Our linear term is 2x. Half of 2 is 1, and 1 squared is 1. We add 1 into the set of parenthesis. But we actually added into the parenthesis is +1(-2). The -2 out front is a multiplier and we cannot ignore it. Adding in to both sides looks like this:
. Simplifying gives us this:
On the left we have created a perfect square binomial which reflects the h coordinate of the vertex. Stating this binomial and moving the -3 over by addition and setting the polynomial equal to y:
From this form,
you can determine the coordinates of the vertex to be (1, 3)
It is 4pi/7, or b. Just want to help ;)
Answer:
5
Step-by-step explanation:
Lila did it correctly. The answer is 324
Following PEMDAS, we first focus on the parenthesis. So we simplify 9-3 to get 6
So we go from
18*4^2+(9-3)^2
to
18*4^2+6^2
The next step is applying exponents. In this case, squaring the terms, so we go from
18*4^2+6^2
to
18*16+36
Next is multiplying
18*16+36
turns into
288+36
Finally, add up 288 and 36 to get 288+36 = 324
That confirms that Lila is correct
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The error that Rob made is that he computed 18*4^2+9^2-3^2 but it is NOT correct. Saying (x-y)^2 = x^2-y^2 isn't a true equation for all x and y. Again you have to simplify what is in the parenthesis first, and then you can square it. Or you must use the FOIL rule to expand out (9-3)^2
It would be B. 28 square yards
