The numbers of new CDs is 30 and the old CDs is 21.
To solve this problem, we have to write a system of equations in which we would know the numbers of each types of CD she bought.
<h3>System of Equations</h3>
This is used to solve a series or complex of word problems in which we can represent in a mathematical statements;
- Let n represents numbers of new CDs
- Let u represents numbers of old CDs
The equations can be represented as
Let's take equation (i)
Making n the subject of formula
we can put equation (iii) into equation (ii)
Let's put the value of u into equation (i)
From the calculations above, the numbers of new CDs is 30 and the old CDs is 21.
Learn more on system of equations here;
brainly.com/question/13729904
Answer:
x = 110°
Step-by-step explanation:
The Outside Angle Theorem states that the measure of the angle formed by two secants or a secant and tangent from a point outside of a circle is half the difference between the two arcs.
This means that ½ (210 – x) = 50.
½ ( 210 – x ) × 2 = 50 × 2
210 – x = 100.
210 – x + x = 100 + x.
210 = 100 + x.
100 + x = 210.
100 + x – 100 = 210 – 100.
x = 110.
This value must be true because:
½ ( 210 – 110 ) = 50.
½ ( 100 ) = 50.
50 = 50.
Answer:
6 quarters, 3 dimes, and 12 nickles
Step-by-step explanation:
Let's say Q is the number of quarters, D is the number of dimes, and N is the number of nickles.
From the information in the problem, we can write three equations:
25Q + 10D + 5N = 240
N = 2Q
Q = 2D
Solve the system of equations using substitution.
25(2D) + 10D + 5(2Q) = 240
50D + 10D + 10Q = 240
60D + 10(2D) = 240
60D + 20D = 240
80D = 240
D = 3
Q = 6
N = 12
There are 6 quarters, 3 dimes, and 12 nickles.
Step-by-step explanation:
perimeter 4+4+1+1 = 10
hope it helps
