Answer:
see explanation
Step-by-step explanation:
Given
9n² - n - 
= 0 ← multiply through by 3 to clear the fraction
27n² - 3n - 2 = 0 ← factoring
Consider the factors of the product of the n² term and the constant term which sum to give the coefficient of the n- term
product = 27 × - 2 = - 54 and sum = - 3
The factors are - 9 and + 6
Use these factors to split the n- term
27n² - 9n + 6n - 2 = 0 ( factor the first/second and third/fourth terms )
9n(3n - 1) + 2(3n - 1) = 0 ← factor out (3n - 1) from each term
(3n - 1)(9n + 2) = 0
Equate each factor to zero and solve for n
3n - 1 = 0 ⇒ 3n = 1 ⇒ n = 
9n + 2 = 0 ⇒ 9n = - 2 ⇒ n = - 
The McLean family could drive 220 miles in four hours.
Answer:
x = -30
y = -20
Step-by-step explanation:
x - 12y = 210..... (I)
x - 6y = 90..... (II)
Subtract equation (II) from (I)
- 12y - (-6y) = 210 - 90
-12y + 6y = 120
-6y = 120
Divide through by -6y
Therefore, y = -20
Substitute y = -20 in equation (II)
x -6 (-20) = 90
x + 120 = 90
x = 90 - 120
x = -30
Hope that helped
Answer: 306 cm^2
Step-by-step explanation:
Surface is found by add all the areas of the sides together, including sides, top and bottom. You might need to divide the 3D shape into different shapes in order to find the area of the sides/top/bottoms. Area for rectangle = bxh.
Answer:
20
Step-by-step explanation:
You do have some idea of how the question is done. It won't take much to learn the right answer.
braces = square root( length^2 + height^2)
braces = √( (12)^2 + (16)^2) )
braces = √(144 + 256)
braces = √(400)
braces = 20
