3x-4 is the answer, you have to see that if its 3 times her nieces age it would be 3x and if its four less than that it is 3x-4
Answer:
X 1 = -4,X 2 =12
EXPLANATION:
Determine the defined range
X+6/x=6/x-8,x#0,x#8
Simplify the equation using cross-multiplication
(X+6) x (x-8)=6x
Move variable to the left-hand side and change its sign
(X-6)x(x-8)-6x=0
Multiply the parentheses
X^2-8x+6x-48-6x=0
Since two opposites add up to zero, remove them from the expression
X^2-8x-48=0
Write -8x as a difference
X^2+4x-12x-48=0
Factor out x from the expression
Xx(x+4)-12x-48=0
Factor out -12 from the expression
Xx(x+4)-12(x+4)=0
Factor out from the expression
(x+4)x(x-12)=0
When the product of factors equals 0, at least one factor is 0
x+4=0
x-12=0
Solve the equation for x
X=-4
X-12=0
X=-4,x#0,x#8
Check if the solution is in the defined range
X=-4
x=12
The equation has 2 solutions
X 1 = -4,X 2 =12
Hope this helps
Hello from MrBillDoesMath!
Answer:
4
Discussion:
As vertical angles are equal, Angle 3 = Angle 2, so
Angle 3 = 3x + 2 (A)
Angles 3 and 7 are corresponding angles and hence equal. So
Angle 3 = Angle 7 => use (A) above and Angle 7 = x + 10
3x + 2 = x + 10 => subtract x from both sides
3x -x + 2 = x - x + 10 =>
2x + 2 = 10 => subtract 2 from both sides
2x = 10 -2 = 8
x = 8/2 = 4
which is the first choice
Thank you,
MrB