Answer:
The x-axis
Step-by-step explanation:
When the y-value is 0, x value can be anything from -∞ to ∞. So, any solution would lie on the x-axis only when y = 0.
The equation that you must use is y=15x+15
so x would be 1,2,3,4,5 and y would be 30,45,60,75,90
Given:
The equations are


To find:
Which function is changing more quickly.
Solution:
The slope intercept form of a line is

Where m is slope and b is y-intercept.
On comparing
with the slope intercept form, we get



On comparing
with the slope intercept form, we get


Since,
, it means the absolute rate of change of second function is greater than the first function.
Therefore, the second function is changing more quickly.
Answer:
x = -2, y=1
Step-by-step explanation:
x-7y=-9---------------------equation 1
-x+8y=10-------------------equation 2
From equation 1, make x the subject of formula
x=7y-9----------------------equation 3
substituting x=7y-9 in equation 2,
-(7y-9)+8y=10
Expanding bracket
-7y+9+8y=10
Collecting like terms
8y-7y=10-9
y=1
substituting y=1 in 3
x=7(1)-9
x=7-9
x=-2
280 divided by 7 = 40 pages every night
(28/7=4, add a zero)