Answer:
Step-by-step explanation:
<u>Given</u>
<u>Solving</u>
- To find f(3), substitute x = 3 in the function
- ⇒ f(3) = -2(3)² + (3) + 5
- ⇒ f(3) = -2(9) + 8
- ⇒ f(3) = -18 + 8
- ⇒ <u>f(3) = -10</u>
Set up the equation by writing the number of students in the ratio as a fraction:
3/4= (245-x)/x Cross multiply:
3x= 4(245-x) Multiply on right:
3x= 980-4x Add 4x on both sides:
7x= 980 Divide both sides by 7:
x= 140 this is how many girls there are. And:
245-140= 105= boys
You need help With what exactly?
The 3rd selection is appropriate.
.. 5b +1 = a = 3b +5
by the transitive property of equality,
.. 5b +1 = 3b +5
4 to 7
or
4+7= 12
4x+7x=33
x=3
so,
(4×3)+(7×3)=33
12+21=33
or
12 and 21.
hope it helped
