Answer:
141 5/7
Step-by-step explanation:
8c + 10b ÷ 7a
Let c = 7, b = 12, and a = 5
8*7 + 10*12 ÷ 7*5
Multiply and divide from left to right
56+120 ÷7*5
56+ 600/7
Get a common denominator
392/7 + 600/7
992/7
Change from an improper fraction to a mixed number
141 5/7
To complete a square for ax²+bx+c, you first make a=1.
in this case, a is already 1
move c to the right side: x²+14x=-47
next, add (1/2 of b)² to both sides, in this case, b=14, half of 14 is 7, so x²+14x+ 7²=-47+7²
the left side is now a perfect square: (x+7)²=2
x+7=√2 or x+7=-√2
x=√2-7, or x=-2-√7
Answer: Option D. y+2x=3
Solution
If a line with a slope of -2:
Slope: m=-2
crosses the y-axis at (0,3):
(0,3)=(0,b)→b=3
What is the equation of the line?
y=mx+b
Replacing the known values:
y=-2x+3
Adding 2x both sides of the equation:
y+2x=-2x+3+2x
y+2x=3
5:16 is no
24:15 is no
3:12 is yes