MATH HELP-- I have no idea how to do this

Let's say 'Mowed Lawns' is L
And 'Walking Dogs' is D

So we do this..
•10L + 4D = 62 (10 hours of mowing lawn + 4 hours of walking dogs = 62$)
• 8L + 5D = 55 (8 hours of mowing lawn + 5 hours of walking dogs = 55$)

Now we have a to equations..
10L + 4D = 62
8L + 5D = 55

= 10L + 4D = 62 x 5
8L + 5D = 55 x4

=50L + 20D = 310
32L + 20D = 220

Subtract them away from each each other
=50L + 20D = 310
- 32L + 20D = 220

=18L = 90
L = 90 ÷ 18
L = 5

So he gets payed 5$ for mowing the loan...

Now we find out D
We use
8L+ 5D = 55
=8(5) + 5D = 55
= 40 + 5D = 55
=5D = 55 - 40
=5D = 15
=D = 15 ÷ 5
D = 3

So he gets payed 3$ for walking dogs

Sooo...
He gets payed 5$ an hour for mowing the lawn
And gets payed 3$ an hour for walking dogs

Let L be the amount he charges for lawns.
Let d be the amount he charges for dogs.
then
10L + 4d = 62
8L + 5d = 55
usually it is fastest to eliminate a variable by subtracting
so multiply first equation by 5 and second by 4

50L + 20d = 310
32L + 20d = 220

now subtract

18L = 90
L = 90/18 = 5

then substitue into first equation
10*5 + 4d = 62
4d = 62-50 = 12
d = 3

check with second equation
8(5) + 5(3) = 40 + 15 = 55

10L+4D=62
8L+5D=55
10L+4D=62

D=2L-7
10L+4(2L-7)=62
10L+8L-28=62
18L=90
L=5
D=3
$5 per hour to mow lawns and $3 per hour to walk dogs