Easy Algebra Step-by-Step

212 Easy Algebra Step-by-Step

Exercise 20

For 1–3, solve by the substitution method.

1. xy
   xy

24 yy=−

27 xy+=y

2. 43
   313

xy

xy 33

3. 428
   23 8

xy

xy 3

22 y=

3 y=−

For 4–6, solve by the elimination method.

4. − =
   −

24 + 8

27 =−

xy+ 4

xy−

5. 826
   313

xy 2

xy 3

2 y=

3

6. 24
   46 16

xy

xy 66 y=−

For 7 and 8, estimate solutions by using the graphing method.

7. 323
   629

xy 2

xy 2

2 y=

22 y=

8. 7142
   14 711

xy 1

xy 7

1144 y

7