Answer:
x ≈ 1.32, x ≈ - 5.32
Step-by-step explanation:
Given
x² + 4x - 7 = 0 ( add 7 to both sides )
x² + 4x = 7
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 7 + 4
(x + 2)² = 11 ( take the square root of both sides )
x + 2 = ± 
( subtract 2 from both sides )
x = - 2 ± 
Thus
x = - 2 - ≈ - 5.32 ( to 2 dec. places )
x = - 2 + ≈ 1.32 ( to 2 dec. places )
First, convert "of" to x and put this info into an equation:
Let n represent the unknown number.
14.4 % x n= 10.4
n = 10.4 / 14.4%
n = 72.22222
n = ~72
Hope this helps!
Answer:
The last one is the answer
Answer:
The number is 72.
Step-by-step explanation:
Let the digits be x and x - 5 where x is the first digit.
(As the number reversed = 3/8 of the original number the first digit must be the largest),
Consider the reverse digit number:
The original number = 10x + (x - 5) so the reverse number is 10(x - 5) + x and
10(x - 5) + x = 3/8(10x + (x - 5))
11x - 50 = 3/8(11x - 5)
11x - 50 = 33/8 x - 15/8 Multiply through by 8:
88x - 400 = 33x - 15
55x = 385
x = 7
and x-5 = 2.
