Answer:
A. (-7 -2)
Step-by-step explanation:
You can eliminate y by multiplying the first equation by 7 and subtracting 6 times the second equation:
7(-3x +6y) -6(5x +7y) = 7(9) -6(-49)
-21x +42y -30x -42y = 63 +294 . . . . eliminate parentheses
-51x = 357 . . . . . . . . collect terms
x = -7 . . . . . . . divide by -51. This matches answer choice A.
Answer:
a₁ = 38
Step-by-step explanation:
Given AP, where:
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<h3>Solution</h3>
aₙ = a₁ + (n-1)d
- a₈ = a₁ + 7d = a₁ + 7*(-2) = a₁ - 14
- a₁₂ = a₁ + 11d = a₁ + 11*(-2) = a₁ - 22
8a₈ = 12a₁₂
- 8(a₁ - 14) = 12(a₁ - 22)
- 2(a₁ - 14) = 3(a₁ - 22)
- 2a₁ - 28 = 3a₁ - 66
- 3a₁ - 2a₁ = -28 + 66
- a₁ = 38
Answer:
Step-by-step explanation:
Step 1: -3(x+2y=3)
Step 2: -3x-6y=-9
Step 3: 3x cancels out with -3x
Step 4: add 2y and -2y, and add 3 and 5
Step 5: the answer is NO SOLUTION or INFINITE SOLUTION
the correct answer is -448