Note that Cheryl wants to find the number of hours <u>seventh grade boys and girls</u> spend on homework each week.
There are multiple causes of a biased sample. Two of the most obvious ones I find are:
1. She's surveying <u>girls</u>, but she is trying to get data on the number of hours <em>all</em> seventh graders (boys <em>and</em> girls) spend.
2. She's surveying 50 girls from the <u>entire school</u>, although she is trying to get data on seventh graders only.
-32=2(x^2+10x)
-32=2x^2+20x
-2x^2-20x-32=0
-2(x+2)(x+8)=0
therefore,
x+2=0 or x+8=0
so,...... x= -2 or -8
Selection A is appropriate.
_____
When the coefficient of x^2 is negative, the graph opens down.
Answer:
b
Step-by-step explanation:
so 17 squared minus 8 squared is 225. the square root of 225 is 15
Answer:
Step-by-step explanation:
This is called a 'System of equations'.
Say that you have these two expressions, and the unknown is "b".
5b = y
4b+2 = y
Now we can solve two ways; graph it or solve it.
Solving it, we can see that they both equal y, so:
5b=4b+2
move 4b to the left side by subtraction:
(5b-4b) =2
b = 2
let's see what y equals when b = 2
5 * 2 = y
10 = y
Graphing it we see they intersect, or solve at
(2,10) or b=2, y=10
Hope this helps!