A quadratic in vertex form reads as
(<em>x</em> - <em>a</em>)² + <em>b</em>
where (<em>a</em>, <em>b</em>) is the vertex.
To get the given quadratic in this form, complete the square:
<em>x</em>² - 6<em>x</em> - 40 = <em>x</em>² - 6<em>x</em> + 9 - 49 = (<em>x</em> - 3)² - 49
Or, work backwards by expanding the vertex form and solving for <em>a</em> and <em>b</em> :
(<em>x</em> - <em>a</em>)² + <em>b</em> = <em>x</em>² - 2<em>ax</em> + <em>a</em>² + <em>b</em>
So if
<em>x</em>² - 6<em>x</em> - 40 = <em>x</em>² - 2<em>ax</em> + <em>a</em>² + <em>b</em>,
then
-2<em>a</em> = -6 → <em>a</em> = 3
<em>a</em>² + <em>b</em> = -40 → <em>b</em> = -49
Answer:
(If you were asking for the answer for question 7)
c. Initially, Cassie has $20 in her account.
Step-by-step explanation:
-20 represents the slope or rate of change of the line and 275 represents the y-intercept or starting point of the line on the y-axis. C is the right answer because initially Cassie had $275 in her account, not $20.
Answer:
$99
Step-by-step explanation:
11.49 is estimated to 11
9.3 is estimated to 9
1 yard cost $11 what of 9
11×9=99
Answer:
$12
Step-by-step explanation:
His 4 late fees took -48 so I just divided the amount to the number of fees
