Multiply both sides usuinf the fraction
Answer:
Postcards bought was 9
Step-by-step explanation:
<h3>
<u>P = 3D</u></h3>
where,
- P = total number of postcards
- D = days of vacation = 3 days
⟼ P = 3D
prince number of days of vacation is 3 therefore we multiply 3 by 3
⟼ P = 3(3)
multiply 3 by 3
⟼ P = 9
Jared bought 9 postcards
15 gallons of 35% peroxide solution contains 0.35 × 15 = 5.25 gallons of hydrogen peroxide. The rest of the volume is made up of 15 - 5.25 = 9.75 gallons of water.
If we add 
gallons of water to the solution, the amount of hyrdrogen peroxide in the solution stays the same, but the volume of water increases to 
gallons, and the total volume increases to 
gallons.
To get a concentration of 8% in this diluted solution, we add gallons of water such that
Solve for .
To get the desired concentration, one must add 50.625 gallons of water, and one will end up with a total volume of 65.625 gallons of solution.
Remember your prefixes! They help a lot, because there is a formula for this particular problem. Nonagon refers to a shape with 9 sides.
The number of triangles a polygon has is represented by the formula:
(n-2)
Where "n" is the number of sides. If you ever forget what you subtract "n" by think of a triangle. It has 3 sides, so it is only logical that you should only have 1 triangle (subtract by 2). So, what is the sum of the interior angles of a triangle, 180°. So the formula looks like this:
Sum of Interior Angles = 180°(n-2)
180°(9-2)
180°(7) = 1260° is the sum of interior angles for a nonagon!
11 = -3k - 22 - 8k....combine like terms on the right side
11 = -11k - 22 ...add 22 to both sides
11 + 22 = -11k
33 = -11k....divide both sides by -11
-33/11 = k
-3 = k <===
