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:
the asnwer is C
Step-by-step explanation:
Answer:
step 2
and then also in step 3 compensating the error in step 2
Step-by-step explanation:
I think I just answered this for another post.
sin(a - b) = sin(a)cos(b) - cos(a)sin(b)
so, step 1 is correct :
sin(A - 3pi/2) = sin(A)cos(3pi/2) - cos(A)sin(3pi/2)
but step 2 suddenly and incorrectly switched that central "-" to a "+".
yes, sin(3pi/2) = -1, but that is still an explicit factor in step 2. so it was not used to flip the central operation from subtraction to addition, and therefore this change was a mistake.
then, in step 3, another error was made by just ignoring the "-" sign of "-1" and still keeping the central "+" operation. this error compensated for the error in step 2 bringing us back by pure chance to the right result.
Answer:
The answer can be calculated by doing the following steps;
Step-by-step explanation:
