Answer:
x=1+2√2 or x=1−2√2
Step-by-step explanation:
Let's solve your equation step-by-step.
3x2−6x=21
Step 1: Since the coefficient of 3x^2 is 3, divide both sides by 3.
3x2−6x
3
=
21
3
x2−2x=7
Step 2: The coefficient of -2x is -2. Let b=-2.
Then we need to add (b/2)^2=1 to both sides to complete the square.
Add 1 to both sides.
x2−2x+1=7+1
x2−2x+1=8
Step 3: Factor left side.
(x−1)2=8
Step 4: Take square root.
x−1=±√8
Step 5: Add 1 to both sides.
x−1+1=1±√8
x=1±√8
x=1+2√2 or x=1−2√2
The volume of the tuna can is 663.66 cm^3.
Hope that helps!
Answer:
The effect of doubling all the dimensions of a triangular pyramid will have on the volume of the pyramid is to increase it by 8 times.
Step-by-step explanation:
i) volume of triangular pyramid = Area height
= (Base of triangle perpendicular height of triangle) height
ii) if we double all the dimensions then the three variables((Base of triangle, perpendicular height of triangle, height of pyramid) will be doubled
and the volume of the new pyramid will be 8 times that of the original one.
<h3>
Answer: 15 years old</h3>
=============================================
Explanation:
m = Maggie's age (some positive whole number)
4m = four times her age
4m-7 = seven years younger than 4m = brother's age
Add up her age (m) and her brother's age (4m-7) to get a sum of 68.
m+(4m-7) = 68
5m-7 = 68
5m = 68+7
5m = 75
m = 75/5
m = 15
Maggie is currently 15 years old.
Her brother is currently 4m-7 = 4*15-7 = 60-7 = 53 years old.
Their current year ages add to: 15+53 = 68 which confirms the answer.