So, you have to have your equation in terms of dimes. What you said about what he has: four more nickels than dimes in his pocket. Will help with our equation.
We know what a nickel and dime is worth. A nickel is .05 and a dime is .1
We don't know how many dimes are in his pocket, since we're trying to solve it.
.1x+(4+x).05=1.25;
In the parenthesis, it shows how there are four more nickels. Let's solve it now.
.1x + (4+x).05=1.25
.1x + .2+ .05x = 1.25; Let's add like terms.
.15x + .2 = 1.25; Subtract .2 from both sides.
.15x= 1.05
1.05÷.15= 7 =x
There are 7 dimes in his pocket, let's check our answer.
We now know there are 11 nickels, since there are four more nickels than dimes.
11(.05) +.1(7) = 1.25
.55+ .7 = 1.25
Now that we've tried it, we know there are 7 dimes in his pocket.
Tell me if this helps!
Diagonals that bisect each other are perpendicular and form a right angle.
AEB is a right triangle.
We can apply the Pythagorean theorem:
c^2 = a^2+b^2
Where c is the hypotenuse (longest side) and a and b the other 2 legs.
Replacing:
AB^2 = AE^2+BE^2
AB^2 = 5^2+12^2
AB^2 = 25+144
AB^2 = 169
AB=√169 = 13
Lenght of AB= 13
First, let's multiply the first equation by two on the both sides:
<span>8x + 7y = 39 /2
</span>⇒ 16x + 14y = 78
Now, the system is:
<span>16x + 14y = 78
</span><span>4x – 14y = –68
</span>
After adding this up in the column:
(16x + 4x) + (14y - 14y) = 78 - 68
20x = 10
⇒ x = 10/20 = 1/2
y can be calculated by replacin the x:
<span>8x + 7y = 39
</span>⇒ 8 · 1/2 + 7y = 39
4 + 7y = 39
7y = 39 - 4
7y = 35
⇒ y = 35 ÷ 7 = 5
Answer: 4.75
Step-by-step explanation:
Answer:
80 is less than or equal to 22+7x
8 DVDs
Step-by-step explanation:
I don't have the inequality signs sorry if you don't know its the symbol thats opening to the left with a line underneath
80 is less than or equal to 22+7x
subtract 22
58 is less than or equal to 7x
divide and flip the sign to the right
x is greater than or equal to 8.29
so he can buy 8 DVDs in total
