Answer:
15a-21
Step-by-step explanation:
could be wrong though
So in this case, we have to replace the known value.
y=3
y=-2x+3
3=-2x+3
Then we leave our unknown value alone.

= x
In this case, our x value would be 0.
We check it...
3=-2(0)+3
3=0+3
3=3
So y=3 x=0
For the second one we have...
y=3x+2
y=-3x-4
For this we substitute the y in any of the equation...
3x+2=-3x-4
We move the unknown values to one side and the ones without unlown values to the other side...
3x+3x=-4-2
Then we solve
6x=-6
Then we leave the unknown value alone.
x=

Then solve for x.
x= -1
Then for our y value we return to one of the original equations and substitute the x value.
y=3x+2
y=3(-1)+2
y=-3+2
y=-1
y=-3x-4
y=-3(-1)-4
y=3-4
y=-1
So in this case we got that x= -1 and y= -1
Answer: Length of AB is 16 cm
Step-by-step explanation:
Given: Diameter of a circle is 20 cm and CE = 4 cm
Now as shown in figure AO, BO, CO are radii

Therefore
AO=BO=CO= 10 cm
Now

Now in Δ OEB
∠OEB =90°
Therefore by Pythagoras theorem : In a right angle triangle the square of hypotenuse is equal to the sum of square of other two sides.
So we have

Now as we know perpendicular to the chord from the center of a circle bisect the chord.
Therefore

Hence , the length of AB is 16 cm .
I believe that it is B. Hope this helps!