Answer:
4.2
Step-by-step explanation:
84 divided by 20 4.2
Answer:
(8.5, - 2 )
Step-by-step explanation:
Given the 2 equations
6x + 4y = 43 → (1)
2x - 3y = 23 → (2)
Multiplying (2) by - 3 and adding to (1) will eliminate the term in x
- 6x + 9y = - 69 → (3)
Add (1) and (3) term by term to eliminate x, that is
13y = - 26 ( divide both sides by 13 )
y = - 2
Substitute y = - 2 in either of the 2 equations and solve for x
Substituting into (1)
6x + 4(- 2) = 43
6x - 8 = 43 ( add 8 to both sides )
6x = 51 ( divide both sides by 6 )
x = 8.5
Solution is (8.5, - 2 )
Answer:
-5/3
Step-by-step explanation:
(0,8) (3,3)
Let x is Casey's sister age.
<span>3 years ago:
</span><span>Casey was twice as old as his sister: 2a - 3
Now:
</span><span>he is 5 years older than his sister: a + 5
2a - 3 = a + 5
subtract a to both sides
2a - 3 -a = a + 5 - a
simplify
a - 3 = 5
add 3 to both sides
a - 3 + 3 = 5 + 3
simplify
a = 8
His sister age is 8 years old now.
</span>Now:
he is 5 years older than his sister: a + 5 = 8 + 5 = 13
<span>
proof:
so 3 years ago,
his sister age: 8 - 3 = 5
Casey age 3 years ago:
13 - 3 = 10 (</span>C<span>asey was twice as old as his sister 3 years ago</span>)
<span>
Answer:
Casey is 13 years old now.
</span>