Answer:
The "number" is 26
Step-by-step explanation:
if x is the number...
8x - 22 = 186
8x - 22 + 22 = 186 + 22
8x = 208
x = 26
Since 25% is smack in the middle between 20% and 30%, it will take equal volumes of ech to make a 25% solution.
Since 4 gallons of 30% solution was used, so 4 gallons of 20% solution will be needed.
Answer:
x + 3y + 9 = 0
Step-by-step explanation:
y=3x + 2
Coefficient of x = 3
Gradient (m) of line y= 3x + 2 is 3
Since the line passing through point
(3,-4) is perpendicular to line y=3x + 2
hence gradient (m) of the line is -1/3;
And hence it equation is given as;
y - y1 = m(x - x1)
y - (-4) = -1/3(x - 3)
multiplying through by 3;
3 × y + 3 × 4 = 3 × -1/3(x - 3)
3y + 12 = -1(x - 3)
3y + 12 = -x + 3
x + 3y + 12 - 3 = 0
x + 3y + 9 = 0
