F(0) is a y-intercept.
f(0) = -6
Ratio:
Red : Total
2 : 5
(x2) (x2)
4 : 10
Green : Total
3 : 10
Total of red and green marbles = 4 + 3 = 7
Blue marbles = 10 - 7 = 3
10 parts = 40 marbles
1 part = 40 ÷ 10 = 4
3 parts = 4 x 3 = 12
Answer: There are 12 blue marbles.
L = liz's age now
J = Jack's age now
L-1 and J-1 are their ages one year ago
L-1=3(J-1)
L-1=3J-3
L=3J-3+1
L=3J-2 (to be used later)
L+2 and J+2 are their ages in two years
L+2=2(J+2)
replace L by 3J-2
3J-2+2=2(J+2)
3J=2J+4
3J-2J=4
J=4 is Jack's age now
L-1=3(J-1)
L-1=3(4-1)
L-1=3*3
L-1=9
L=9+1
L=10 is Liz's age now
Use slope intercept form for equation, which is y = mx +b. m is slope and b is the y-intercept.
Find slope by change in y over change in x. So pick two points, for example (0, 24) and (2, 20). Slope (m) will be
(y2-y1)/(x2-x1)
= (24-20)/(0-2)
= 4/-2
m = -2
Y-intercept is 24.
Equation is y = -2x + 24
