Answer + Step-by-step explanation:
1) D be the symmetric of B with respect to C then CD = BC
A the symmetric of C with respect to B then AB = BC
We obtain :
CD = BC
AB = BC
Then AB = CD
2) m∠SBA = 180 - SBC = 180 - SCB = m∠SCD
3) we have :
BA = CD
BS = CS
m∠SBA = m∠SCD
Then
the triangles SBA and SCD are congruent
4)
the triangles SBA and SCD are congruent Then SA = SD
Therefore SAD is an isosceles triangle.
Direct variation mean x =ky so y = x/k
(2,14) mean y = kx so 14 = k*2 so 14 = 7*2 so 14 = 14
(4,28) mean y = kx so 28 = k*4 so 28 = 7*4 so 28 = 28
from these result that the 3rd choice is right sure
38b + 61t = 791.50....multiply by 27
54b + 50t = 923.....multiply by -19
-------------------
1026b + 1647t = 21370.5 (result of multiplying by 27)
-1026b - 950t = - 17537 (result of multiplying by -19)
------------------add
697t = 3833.50
t = 3833.50 / 697
t = 5.50 <=== cost of each towel
38b + 61t = 791.50
38b + 61(5.50) = 791.50
38b + 335.50 = 791.50
38b = 791.50 - 335.50
38b = 456
b = 456/38
b = 12 <== cost of each bed sheet
so the cost of 1 towel and 1 bed sheet is : 12 + 5.50 = 17.50
You start with the greater number when adding on a number line simply for convenience.
Put it this way:
Would you rather add more to a small number or add less to a large number?
Naturally people would choose to add less to a large number because that way you do not have to do so much work. So, you would start with the greater number when adding on a number line.