D) is the answer i already done that question
Answer:
x=80
Step-by-step explanation:
To find the average, we take the numbers, add them up. Then divide by the number of terms we added.
Let x= the unknown number
The average =90
Average = (138+40+102+x)/4
90 = (138+40+102+x)/4
Multiply by 4 on each side
90*4 =(138+40+102+x)/4 *4
360 = (138+40+102+x)
Combine like terms
360 = 280 +x
Subtract 280 from each side
360-280 = 280+x-280
80 =x
Step-by-step explanation:
I'll do line A for you and you can use the formulas to solve lines B and C yourself, since its good for you to practice doing these questions yourself
a)
The gradient, m, is calculated using m = (y2-y1)/(x2-x1) where x1,x2,y1 and y2 can be any ordered pairs on the line. I'm going to use (4,0) and (7,3) as the 2 points.
m = (3-0)/(7-4) = 3/3 = 1
b)
The y-intercept is where the line intersects with the x-axis. In this case (0,-4)
c)
The equation of a linear line is y=mx+b (or c depending on which country you are from)
y = 1x-4
y=x-4
Now try the other 2 lines yourself!
If this answer has helped you, considered making this the brainliest answer!
The 65 tens blocks can be solved by doing 65x10 which is 650. the 7 ones blocks can be solved by 1x7 which is 7 so you then add up 650 and 7 to get a grand total of 657