Lizbeth has 38 coins consisting of nickels, dimes, and quarters. The total value of the coins is $6.40. The number of quarters if three more than three times the number of dimes. How many of each type of coin does Lizbeth have? PLEASE EASY 25 POINTS.

21 quarters, 6 dimes, and 11 nickels

Step-by-step explanation:

# of Quarters = x.

# of Dimes = y.

# of Nickels = z.

(i)x = 3y+3.

(ii) 0.25x + 0.1y + 0.05z = 6.4

(iii) x + y + z = 38.

Multiplying (iii) by -0.05, and adding it to (ii),

we then get:

0.2x + 0.05y = 4.5.

Now plug in (i) into this.

0.65y + 0.6 = 4.5.

0.65y = 3.9

y = 6.

Since y = 6, we can subsitute this into our equation.

0.2x + 0.3 = 4.5

0.2x = 4.2

x = 21.

Since x = 21, y =6, then z = 11.

let's add {f(x)=x+1}f(x)=x+1 and {g(x)=2x}g(x)=2x together to make a new function.

f(x)+g(x) =(x+1)+(2x)=x+1+2x=3x+1

let's call this new function hh. so we have:

{h(x)}={f(x)}+{g(x)}{=3x+1}h(x)=f(x)+g(x)=3x+1

we can also evaluate combined functions for particular inputs. let's evaluate function hh above for x=2x=2. below are two ways of doing this.

method 1: substitute x=2x=2 into the combined function hh.

h(x)

h(2)

​    

=3x+1

=3(2)+1

=7

​ since h(x)=f(x)+g(x)h(x)=f(x)+g(x), we can also find h(2)h(2) by finding f(2) +g(2)f(2)+g(2).

first, let's find f(2)f(2):

f(x)

f(2)

​    

=x+1

=2+1

=3

​  

now, let's find g(2)g(2):

g(x)

g(2)

​    

=2x

=2⋅2

=4

​  

so f(2)+g(2)=3+4=\greend7f(2)+g(2)=3+4=7.

notice that substituting x =2x=2 directly into function hh and finding f(2) + g(2)f(2)+g(2) gave us the same answer!

4.

step-by-step explanation:

it have the same area.brainliest