Answer:
The number of plums = 4
The number of peaches = 16
The number of nectarines = 1
Step-by-step explanation:
Let the number of peaches be = x
Let the number of nectarines be = y
Let the number of plums be = z
A box of fruit has four times more peaches than plums. This means that
The number of peaches = 4 X the number of plums.
i.e x = 4z
The box has 3 fewer nectarines than plums. This means that
Number of nectarines = number of plums - 3
i.e y = z - 3
If the box contains 21 pieces of fruit, this means that if we sum up all the peaches, nectarines, and plums in the box, we will get 21.
Peaches + Nectarines + Plums = 21
4z + z-3 + z = 21
6z =21 +3
z = 24/6
z = 4
Therefore, the number of plums = 4
The number of peaches = 4 X 4 = 16
The number of nectarines = 4 -3 = 1
Answer:
A , B , C
Step-by-step explanation:
1) find the slope of the given line
slope = (-a/b) = (-8/4) = -2
two parallel lines have the same slope
A : correct
B : (-a/b) = -16/8 = -2 (correct)
C : correct
D : wrong (2 is different from -2)
Answer:
- sin(2x) = -4/5
- cos(2x) = 3/5
- tan(2x) = -4/3
Step-by-step explanation:
It may be easiest to start with tan(2x).
tan(2x) = 2tan(x)/(1 -tan(x)²)
tan(2x) = 2(-1/2)/(1 -(-1/2)²) = -1/(3/4)
tan(2x) = -4/3 . . . . . still a 4th-quadrant angle
__
Then cosine can be found from ...
cos(2x) = 1/√(tan(2x)² +1) = 1/√((-4/3)²+1) = √(9/25)
cos(2x) = 3/5
__
Sine can be found from these two:
sin(2x) = cos(2x)tan(2x) = (3/5)(-4/3)
sin(2x) = -4/5
