CF = CD + DF (since D is simply a point on the line, and C to that point added onto F to that point is CF), so 4y-9+2y-7=14. Adding it up, we get 6y-16=14 and adding by 16 we get 30=6y. Dividing both sides by 6, we get y=5. Plugging that into DF, we get 10-7=DF=3
Answer:
D. 60, 45,75
Step-by-step explanation:
For options C and D
For a triangle the sum of the angles must always be equal to 180 degrees
So 180 ≠45+45+80
and
60 +45+ 75= 180
For option A and B
The length of the longer side is equal to the square root of the sum of squares of the other two sides in a triangle.
According to Pythagorus theorem
hypotenuse²= base² + perpendicular²
c²= a²+ b²
90²= 50² + 35²
8100= 2500+1225
8100≠3725
95²= 60²+ 25²
9025= 3600+ 625
9025≠4225
Therefore only D is the correct option
Expand
(4a + 12 = 12 + 4a)
Cancel 4a on both sides
12 = 12
Since both sides are equal there are infinitely many solutions
Process of elimination, cross out d) no solution. But I would best go with C)
The length of the rectangle is = 72 cm
The width of the rectangle is = 56 cm
Area of the rectangle is = 
= 
cm²
As given, the other rectangle has the same area as this one, but its width is 21 cm.
Let the length here be = x
Hence, length is 192 cm.
We can see that as width decreases, the length increases if area is constant and when length decreases then width increases if area is constant.
So, in the new rectangle,constant of variation=k is given by,
or 
Hence, the constant of variation is 
