Answer:

Step-by-step explanation:
Given :

Multiply numerator and denominator by 2 :

[Divide both sides by 5 as it is a common factor]

10 to the 5th power means 5 times zero, place 8 before that and it will be 800000 then multiply with 0.5 it will be 400000. In scientific notation it will be like 4x10 the 5th power.
Percent is out of 100, and 25*4=100. So multiply 16*4=64, so the answer is 64%
Answer:
x = - 3 is extraneous
Step-by-step explanation:
Given
- 1 = x ( add 1 to both sides )
= x + 1 ( square both sides )
x + 7 = (x + 1)² ← distribute right side
x + 7 = x² + 2x + 1 ( subtract x + 7 from both sides )
0 = x² + x - 6 ← in standard form
0 = (x + 3)(x - 2) ← in factored form
Equate each factor to zero and solve for x
x + 3 = 0 ⇒ x = - 3
x - 2 = 0 ⇒ x = 2
As a check
Substitute these values into the equation and if both sides are equal then they are the solutions.
x = - 3 :
- 1 =
- 1 = 2 - 1 = 1 ≠ - 3
x = 2 :
- 1 =
- 1 = 3 - 1 = 2
x = 2 is a solution and x = - 3 is extraneous