x = longer section
y = shorter section
x + y = 109
x = 2y + 10
so we sub in eq 2 into eq 1
2y + 10 + y = 109
3y + 10 = 109
3y = 109 - 10
3y = 99
y = 99/3
y = 33 <=== shorter section is 33 cm
x = 2y + 10
x = 2(33) + 10
x = 66 + 10
x = 76 <=== longer section is 76 cm
7-6a=6-7a
+7a on both sides gives you
7-X= 6
Subtract 7 from both sides
-X= -1
Add the negative sign in front of the x to the -1
X= --1
This will end up to be
x= 1
Answer:
x = 2 + sqrt(2) or x = 2 - sqrt(2) thus B. is your answer
Step-by-step explanation:
Solve for x over the real numbers:
4 x^2 - 16 x + 8 = 0
Hint: | Write the quadratic equation in standard form.
Divide both sides by 4:
x^2 - 4 x + 2 = 0
Hint: | Solve the quadratic equation by completing the square.
Subtract 2 from both sides:
x^2 - 4 x = -2
Hint: | Take one half of the coefficient of x and square it, then add it to both sides.
Add 4 to both sides:
x^2 - 4 x + 4 = 2
Hint: | Factor the left-hand side.
Write the left-hand side as a square:
(x - 2)^2 = 2
Hint: | Eliminate the exponent on the left-hand side.
Take the square root of both sides:
x - 2 = sqrt(2) or x - 2 = -sqrt(2)
Hint: | Look at the first equation: Solve for x.
Add 2 to both sides:
x = 2 + sqrt(2) or x - 2 = -sqrt(2)
Hint: | Look at the second equation: Solve for x.
Add 2 to both sides:
Answer: x = 2 + sqrt(2) or x = 2 - sqrt(2)