Answer:5-b=1/5
Step-by-step explanation:
You need LCD or the least common denominator. For 4 over 8 and 2 over 8 have the same denominators except for 2 over 4. You need to ask yourself what times 4 equals to 8? 4 times 2 equals to 8, so multiply 4x2 for the denominator and for the numerator multiply 2x2. Whatever you do to the denominator you have to do the same thing to the numerator. You multiplied 4x2 for the denominator and 2x2 for the numerator and now your fraction is 4 over 8. Now add 4 over 8+ 4 over 8 which is 8 over 8 or 1. Now add 1+ 2 over 8 which is 1 2/8. If you simplify 1 2/8 it will become 1 1/4.
Hope that helped:D
Answer:
- (-16x² +10x -3) +(4x² -29x -2)
- (2x² -11x -9) -(14x² +8x -4)
- 2(x -1) -3(4x² +7x +1)
Step-by-step explanation:
I find it takes less work if I can eliminate obviously wrong answers. Toward that end, we can consider the constant terms only:
- -3 +(-2) = -5 . . . . possible equivalent
- -10 -5 = -15 . . . . NOT equivalent
- 3(-5) -2(5) = -25 . . . . NOT equivalent
- -9 -(-4) = -5 . . . . possible equivalent
- -7 -(-5) = -2 . . . . NOT equivalent
- 2(-1) -3(1) = -5 . . possible equivalent
Now, we can go back and check the other terms in the candidate expressions we have identified.
1. (-16x² +10x -3) +(4x² -29x -2) = (-16+4)x² +(10-29)x -5 = -12x² -19x -5 . . . OK
4. (2x² -11x -9) -(14x² +8x -4) = (2-14)x² +(-11-8)x -5 = -12x² -19x -5 . . . OK
6. 2(x -1) -3(4x² +7x +1) = -12x² +(2 -3·7)x -5 = -12x² -19x -5 . . . OK
All three of the "possible equivalent" expressions we identified on the first pass are fully equivalent to the target expression. These are your answer choices.
The mean would be the best! The mean is when you add up all of those grades and divide by the amount of exams.
If you're solving it,
504 is the total divided by 6 tests would be 84.
30 + 70 + D = 180
100 + D = 180
D = 80°