Answer:
Step-by-step explanation:
First Question
The top question has 2 solutions because eventually you will have to take the square root of (x - 4)^2. One square root will be plus, and the other minus
(x - 4)^2 - 28 = 8 Add 28 to both sides
(x - 4)^2 -28+28 = 8+28 Collect like terms
(x - 4)^2 = 36 Take the square root.
sqrt( (x - 4)^2 ) = sqrt(36)
x - 4 = +/- 6
=============
x - 4 = + 6
x = 6 + 4
x = 10
============
x - 4 = - 6
x = - 6 + 4
x = - 2
The two solutions are (10,0) and (-2,0)
Second Question
The question is solved correctly up to the point where the square root needs to be taken. It is incorrect at that point.
x^2 - 6x - 7 = 0 Add 7 to both sides.
x^2 - 6x = 7 Add 1/2 the linear term and square it to both sides.
x^2 - 6x + (6/2)^2 = 7 + (6/2)^2 Expand the right
x^2 - 6x + 3^2 = 7 + 9
x^2 - 6x + 9 = 16 express the square on the left
(x - 3)^2 = 16 Take the sqrt of both sides.
x - 3 = sqrt(16)
x - 3 = +/-4
============
x - 3 = 4
x = 4 + 3
x = 7
===========
x -3 = - 4
x = - 4 + 3
x = - 1
==========
Solutions
(7,0) and (-1,0)
Answer:
1. The y-intercept
2. The slope of the equation represent the relationship between the time duration in which Clarissa eats chocolate is 1/10
Step-by-step explanation:
1. The value of the y coordinate at the point which the graph meets the y-axis is called to the y-intercept. It is the value at which the x-coordinate is equal to zero, that is, the coordinate of the point at the y-intercept = (y, 0)
2. Given that Clarissa eats 1 piece of chocolate every 10 seconds, we have the slope of the equation represent the relationship between the time duration in which Clarissa eats chocolate is 1/10.
Answer:
a4 = -12
Step-by-step explanation:
Answer:
a) 78
b) 1275.....
Step-by-step explanation:
.............
Answer:
350 of the students are girls.
Step-by-step explanation:
5+7 = 12
600/12 = 50
50 x 7 = 350