The school choir is going on a trip. They plan on bringing 100 total bottles of water and juice with them. Each bottle of water costs $1 and each bottle of juice costs $2. If they spent $140 on drinks how many bottles of water did they buy? How many bottles of juice?

40 bottles of juice

60 bottles of water

Step-by-step explanation:

let w represent water, let j represent juice. set up a system of equations:

w+2j=140

w+j=100

isolate the w by itself on the bottom equation:

w=100-j

solve the top equation by substitution, substituting 100-j for w:

w+2j=140

100-j+2j=140

100+j=140

j=40

this means that they bought 40 bottles of juice.

to find the amount of bottles of water the bought, substitute 40 for j in either of the equations (i did it in the bottom one, because it's easier):

w=100-j

w=100-40

w=60

so, they bought 60 bottles of water.

b

step-by-step explanation:

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.