Answer:
Step-by-step explanation:
12). By applying Pythagoras theorem in the given right triangle,
Hypotenuse² = (Leg 1)² + (Leg 2)²
x² = 7² + 7²
x² = 2(7)²
x = 
x = 
13). By sine rule,
sin(60)° = 

y = 
y = 18
By cosine rule,
cos(60)° = 

x = 
x = 
14). By applying Pythagoras theorem in the given right triangle,
12² = x² + x²
144 = 2x²
72 = x²
x = √72
x = 6√2
Answer:
D
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
To obtain this form use the method of completing the square.
Given
f(x) = - 0.6x² + 4.2x + 240 ← factor out - 0.6 from the first 2 terms
= - 0.6(x² - 7x) + 240
To complete the square
add/ subtract ( half the coefficient of the x- term)² to x² - 7x
f(x) = - 0.6(x² + 2(- 3.5)x + 12.25 - 12.25 ) + 240
= - 0.6 (x - 3.5)² + 7.35 + 240
= - 0.6(x - 3.5)² + 247.35
with vertex = (3.5, 247.35 )
The maximum value is the y- coordinate of the vertex
Then
f(x) = - 0.6(x - 3.5)² + 247.35 has a maximum value of 247.35
Answer:
all FALSE except 3 and 4
Step-by-step explanation:
Hope this helps
Step-by-step explanation:
Just consider the inequalities an equal sign and do the usual way of solving:
8x - 6 > 12 + 2x
8x - 2x > 12 +6
6x > 18
x > 3
*The only rule that you need to remember is that when you multiply or divide a negative number on both sides, then the inequality sign would be reverse.*
Example:
-x + 3 > -2
-x > -2-3
-x > -5
Multiplying both sides by -1:
x < 5
There are 3 feet in 1 yard, so 90/3 = x cubic yards
x = 30
30 cubic yards is your answer
hope this helps