4/3 USE THE FORMULA TO GET YOUR ANSWER
Answer:
C
Step-by-step explanation:
In this technique, if we have to factorise an expression like ax2+bx+c, we need to think of 2 numbers such that:
N1⋅N2=a⋅c=1⋅−12=−12
AND
N1+N2=b=−1
After trying out a few numbers we get N1=3 and N2=−4
3⋅−4=−12, and 3+(−4)=−1
x2−x−12=x2−4x+3x−12
x(x−4)+3(x−4)=0
(x+3)(x−4)=0
Now we equate the factors to zero.
x+3=0,x=−3
x−4=0,x=4
Answer:
(y - 25) = - 0.25(x - 20)
Step-by-step explanation:
Given that :
Height of candle after burning for 20 minutes = 25 cm
Height after burning for 1 hr (60 minutes) = 10 cm
Height (y) in cm of candle x minutes after being lit:
Using the equation :
(y - y1) = m(x - x1)
m = (change in y / change in x)
Change in height within 60 minutes :
Height at 20 minutes = 25cm
Height after an hour = 10
Change in height per hour = (25 - 10) = 15cm
Hence, m = change in height per minute
15cm / 60 = 0.25cm ( - 0.25) (decrease in height)
y1 = 25 ; x1 = 20
(y - y1) = m(x - x1)
(y - 25) = - 0.25(x - 20)
The answer is D, 40%. I got it by knowing that 3 and 4 were the success numbers and that 0,1, and 2 were unsuccessful and that numbers 3 and 4 are less than half, so I went with 40% and it was right. Good luck apex! Finish strong!
