18/4, 27/6, 36/8 are equivalent
S = a / (a - r)...multiply both sides by (a - r)
S(a - r) = a
Sa - Sr = a
Sa - a = Sr
(Sa - a) / S = r or it could be : (aS - a) / S = r
Answer:
Step-by-step explanation:
Show that if 3x – 7 = 5, then x = 4.
Here, our given statement is 3x – 7 = 5, and we're asked to prove x = 4.
x=4
Statements Reasons
1. 3x – 7 = 5 Given
2. 3x – 7 + 7 = 5 + 7 Addition of 7 to equation (1)
3. 3x + 0 = 5 + 7 Substitution of –7 + 7 = 0 into (2)
4. 3x = 5 + 7 Substitution of 3x + 0 = 3x into (3)
5. 3x = 12 Substitution of 5 + 7 = 12 into (4)
6. 3x⁄3 = 12⁄3 Dividing equation (5) by 3
7. x = 12⁄3 Substitution of 3x⁄3 = x into (6)
8. x = 4 Substitution of 12⁄3 = 4 into (7)
Is there such a thing as being too descriptive? Yep, and that was it, since over half the proof was devoted to telling the reader how to do arithmetic. We'll typically take numerical computation for granted, and write proofs like this:
Answer:
Step-by-step explanation:
The co-ordinates of the rectangle are:
A (8, 6)
B (-4, -10)
C (-8, -7)
D (4, 9)
The Area of Rectangle is Given by: <em>length x breadth </em>= AB x BC
Lengths of AB and BC can be found by distance formula
<em>length</em>(AB) = 
= 
Similarly,
<em>length</em>(BC) = 5
Area of Rectangle = AB x BC = 20 x 5 = 100 square units
