Question

14. (08.06 LC)

Answer 1

14. B Add the equations
Since the equations have x and -x, if you add, it cancels out to 0 and x will be eliminated.

15. 7 weeks, $230 D
30x+20=20x+90
10x+20=90
10x=70
x=7

Plug x in
y=20(7)+90
y=140+90
y=230

16. B
4a+c= 60
a+c=27

16 children and 11 adults since 11+16=27 and 4(11)+16= 44+16=60

Answer 2

Answer:

14) Add the equations to eliminate x.

15)7 weeks, $230

16)11 children and 16 adults

Equation 1: a + c = 27

Equation 2: 4a + c = 60

Step-by-step explanation:

14) To find x and y in the given equations :

y = x + 20

y = –x + 2

Our first step will be to add the two equations so that x is eliminated and we can find y . The option

Add the equations to eliminate x is the correct option.

15)  The given equations are Katie

y = 30x + 20

Pamela

y = 20x + 90

y represents the amount of money in dollars and x represents the amount of time in weeks ,

Using substitution method we have :

30x+20=20x+90

Or 30x-20x=90-20

10x=70 or

x=7 .

Substituting x value in y=30x+20 we  have:

y=30(7)+20

y= 210+20

y=230.

The correct option is 7 weeks, $230.

16) It is given  the total number of adults (a) and children (c)  is 27,

or a+c=27.

Given zoo train ride costs $4 per adult and $1 per child,

Or 4a+c=60.

Subtracting the two equations we have:

4a+c=60

a+c=27

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....................................

3a =33,

Or a=11.

Substituting a value in a+c=27

11+c=27

or c=16.

The correct option is

11 children and 16 adults

Equation 1: a + c = 27

Equation 2: 4a + c = 60