A. The solution is (−2,−3) B. infinitely many solutions

C. no solution

D. The solution is (−3,−2)

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  D.  (-3, -2)

Step-by-step explanation:

The equations have different coefficients for x and y, so will have one solution. The solutions offered are easily tested in either equation.

Using (x, y) = (-2, -3):

  x = y -1  ⇒  -2 = -3 -1 . . . . False

Using (x, y) = (-3, -2):

  x = y -1  ⇒  -3 = -2 -1 . . . .True

  2x = 3y  ⇒  2(-3) = 3(-2) . . . . True

The solution is (-3, -2).

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If you'd like to solve the set of equations, substitution for x works nicely.

  2(y -1) = 3y

  2y -2 = 3y . . eliminate parentheses

  -2 = y . . . . . . subtract 2y

  x = -2 -1 = -3

The solution is (x, y) = (-3, -2).

i leave the calculator work to you.

7. diameter 4 miles, circumference 4π miles

8. radius 0.2 miles, circumference 0.4π miles

[this is a bad problem because the actual radius of a car on the track is less than 0.2 miles so the answer is less than 0.4π miles]

9. radius 6 feet, circumference 12π feet

10. diameter 14 cm, circumference 14π cm

11. diameter 4.8 feet, circumference 4.8π feet

where are the choices?