Inequalities are just like regular equations with only one exception. Which is when yo multiply or divide by a negative number to both sides of the inequality sign you must flip it. But, for this inequality that rule will no apply. So, what I do to make it easier because I know we all see a different sign in an equation and we start to freak out. So, change the inequality sign to an equals sign to get a hang of working with them.
Example of changing an inequality sign to an equals sign:
Addition property of equality
or
Example of keeping the inequality sign
Addition property of equality
Answer:
Below in bold.
Step-by-step explanation:
A. −16x2 + 24x + 16 = 0
-8(2x2 - 3x - 2) = 0
-8(2x + 1 )(x - 2) = 0
x = -0.5, 2.
So the x-intercepts are (-0/5, 0) and (2, 0).
B. As the leading coefficients is negative (-16) the vertex of the graph will be a Maximum.
To find its coordinates we convert the function to vertex form:
f(x) = −16x2 + 24x + 16
= -16(x^2 - 1.5x) + 16
Completing the square on contents of the parentheses:
= -16 [(x - 0.75)^2 - 0.75^2] + 16
= -16(x - 0.75)^2 - 16 * -0.75^2 + 16
= -16(x - 0.75)^2 + 9 + 16
= -16(x - 0.75)^2 + 25.
So the coordinates of the vertex are (0.75, 25)
Answer:
...
against the wind, an airplane travels 3640 km in 7 hours.
with the wind, the same plane travels 6000 km in 6hrs.
...
let speed of plane in still air be x mph
speed of wind be y mph.
..
t=d/r
..
against wind speed = x-y mph
with wond speed = x=y mph
...
3640/(x-y)=7
3640 = 7x-7y
/7
520=x-y.....................1
...
6000/x+y = 6
6000 = 6x+6y
/6
1000=x+y.....................2
...
Add (1) & (2)
2x=1520
/2
x=760 mph speed of plane in still air
...
plug value of x in 2
1000=760+y
100-760=y
240 = y
240 mph speed of wind
It's how far a number is from 0.
( ex.) 6 is 6 away from 0 but so is -6; so the absolute value of 6 is 6 and the absolute value of -6 is 6. the symbol "|" is placed on either side to mean absolute value.
(ex.2) |-6| = 6. -|-6|= -6. |6|=6. and -|6|= -6.
if the negative sign is outside of the symbol then the number will always be negative but if there is no negative sign outside of the symbol it will always be positive, even if it looks lile this. |-6| it would still be positive.
