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Add the 3 ratio portions together: 1 + 4 + 7 = 12
Divide total length by 12:
84/12 = 7
Multiply each ratio portion by 7:
1 x 7 = 7
4 x 7 = 28
7 x 7 = 49
The longest piece is 49 cm
102/159 = x/4
34/53 = x/4
34(4) = x(53)
136 = 53x
136/53 = x
Answer:

Step-by-step explanation:
This is horizontal parabola.
It has a directrix at x=-6.
The vertex is (0,0).
The focus is (6,0)
The equation of this parabola is of the form

Where (p,0) is the focus
By comparison, p=6
Therefore the equation of the parabola is

This implies that

Answer:
30degrees
Step-by-step explanation:
Given
Exterior angle m<CDE = 7x - 19 degrees
interior angles are
m<BCD = 2x - 1
m<DBC = x+10
Since the sum of the interior angles is equal to the exterior, hence;
2x - 1 + x+10 = 7x - 19
3x + 9 = 7x - 19
3x - 7x = -19 - 9
-4x = -28
x = 28/4
x = 7
Get m<CDE
m<CDE = 7x - 19
m<CDE = 7(7) - 19
m<CDE = 49 - 19
m<CDE = 30degrees