Answer:
1. B 2. C
Step-by-step explanation:
1. x^2-18x+(18/2)^2=19+(18/2)^2
(x-18/2)^2=100
(x-9)^2=100
x1= -1 x2= 19
2. x^2=81
x=+-9
x1=-9 x2=9
Answer:
it answer is 3 because it is trigonometry
Answer:
see explanation
Step-by-step explanation:
(a)
Given y is directly proportional to x then the equation relating them is
y = kx ← k is the constant of proportion
To find k use the condition when x = 3, y = 18 , then
18 = 3k ( divide both sides by 3 )
6 = k
y = 6x ← equation of proportion
(b)
(i)
when x = 12 , then
y = 6 × 12 = 72
(ii)
when y = 42
42 = 6x ( divide both sides by 6 )
7 = x
The correct answer is B=4