solve using a system of equations: ellen wishes to mix candy worth $1.70 per pound with candy worth $2.50 per pound to form 40 pounds of candy worth $2 per pound. How many pounds of the more expensive candy should she use?

15 pounds

Step-by-step explanation:

let 'x' = $1.70 candy

let 'y' = $2.50 candy

System:

x + y = 40

1.7x + 2.5y = 40(2)

let 'x' = '40-y'

now substitute '40-y' for 'x' to get:

1.7(40-y) + 2.5y = 80

68 - 1.7y + 2.5y = 80

-1.7y + 2.5y = 12

0.8y = 12

y = 12/0.8

y = 15

check:

1.7(25) + 15(2.5) should equal 80

80 = 80

2. angles qrt and qst both measures 156 degrees.

step-by-step explanation:  

we have been given a diagram of a circle and we are told that measure of arc qvt is 156 degrees.  

we can see from our given diagram that angle qrt and angle qst subtends to arc qvt.

since we know that angles subtended by the same arc at the circumference are always equal.

by angle subtended by same arc theorem, measure of angle qrt and angle qst will be equal to the measure of arc qvt.

therefore, angles qrt and qst both measures 156 degrees and 2nd statement is the correct choice.

the first one

step-by-step explanation:

just id the test.