Answer:
slope= - 5/4
Step-by-step explanation:
Answer:
the slope intersection is xy
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>
in 12 key 5 black keys are appearing so consider x key will appear in 120 keys
120/x = 12/5
solving further,
x= 50
Answer - If the pattern shown continues, 50 black keys appear on a pipe organ with a total of 120 keys!
Answer:

Step-by-step explanation:
Given


Required
Eliminate a
Multiply the first equation by -4

Add to the second equation

Solve brackets

Open bracket


At this point, a has been eliminated;
From the list of given options, the option that answers the question is 