Answer:
x = 
Step-by-step explanation:
Given
+ 
= 1
Multiply through by ab to clear the fractions
bx + ax = ab ← factor out x from each term on the left side
x(b + a) = ab ← divide both sides by (b + a)
x =
Answer:
(1/2,-5/2)
Step-by-step explanation:
Let's say David's age right now is x years
x + 6 = 2(x - 7)
x + 6 = 2x - 14
x = 20
Therefor David is 20 years old
Answer:
x = 30
Step-by-step explanation:
1/2(x+6) = 18
Distribute
1/2 x + 3 = 18
Subtract 3 from each side
1/2x +3-3 = 18-3
1/2x = 15
Multiply each side by 2
1/2x*2 = 15*2
x = 30
Assuming the coin is not weighted and is a fair and standard coin - the chance of flipping head is 1/2. You can either flip head or tails, there are no other possible outcomes.
