There's enough arithmetic involved in this that it is convenient to let a machine solver of some sort figure it out. Most graphing or scientific calculators will work this problem for you (consult the manual for yours). If you insist on doing it by hand, you must compute several average values:
• a1 = the average of sleep hours (h)
• a2 = the average of test scores (%)
• a3 = the average of the product of sleep hours and test scores (h×%)
• a4 = the average of the square of sleep hours (h×h)
a) The equation of your best-fit (least-squared-error) line is then
% = (a3 - (a1×a2))/(a4 - (a1)²)×(h - a1) + a2In numbers, this is
% = 6.33333h + 38.6875b) For h=8, the equation gives
6.33333×8 + 38.6875 ≈
89.4
Answer:
540 degrees
Step-by-step explanation:
The sum of the degrees from a diagram with 5 vertices = 540°
Hope this helps:)

Here's the solution ~



Now we will use this identity in denominator
[ a² - b² = (a + b)(a - b) ]


Answer:
x = 50
Step-by-step explanation:
→ Make the equations equal to each other
2 ( x + 10 ) = 3x - 30
→ Expand brackets
2x + 20 = 3x - 30
→ Minus 3x from both sides
-x + 20 = -30
→ Minus 20 from both sides
-x = -50