A boy gave 2/5 of his marbles to his best friend Jessie, and 1/4 to his sister Jenny. If he had 14 marbles left , how many did the boy have to start with ?

  40

Step-by-step explanation:

The remaining fraction is ...

  1 - 2/5 - 1/4 = 20/20 -8/20 -5/20 = 7/20

If 7/20 of the boy's marbles is 14 marbles, he had 40 to start with.

  (7/20)·marbles = 14

  marbles = (20/7)·14 = 40 . . . . . multiply the above equation by 20/7

step-by-step explanation:

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3