Answer:
21
Step-by-step explanation:
90+15=105
105÷5=21
Equation of an ellipse
→having center (0,0) , vertex (
and covertex
and focus
is given by:

As definition of an ellipse is that locus of all the points in a plane such that it's distance from two fixed points called focii remains constant.
Consider two points (a,0) and (-a,0) on Horizontal axis of an ellipse:
Distance from (a,0) to (c,0) is = a-c = 
Distance from (-a,0) to (c,0) is = a + c = 
a -c + a +c
= a + a
= 2 a →(Option A )
A I think
Step-by-step explanation:
I'm not 100% sure though
Answer:
Step-by-step explanation:
a3 = 2
d = -5
=============
a4 = a3 - 5
a4 = 2 - 5
a4 = - 3
===============
a5 = a4 - 5
a5 = -3 - 5
a5 = - 8
Just take a4 as your answer.
Answer:
347
Step-by-step explanation:
2(3) + 210 = 216
2(3) + 125 = 131
216+131 = 347