Answer:
4
Step-by-step explanation:
You call the number x. Then you do (x-7) * 3=-9.
3x-21=-9
3x=12
x=4
Let's solve your system by substitution.
y
=
3
x
+
5
;
y
=
x
+
19
Step: Solve
y
=
3
x
+
5
for y:
y
=
3
x
+
5
Step: Substitute
3
x
+
5
for
y
in
y
=
x
+
19
:
y
=
x
+
19
3
x
+
5
=
x
+
19
3
x
+
5
+
−
x
=
x
+
19
+
−
x
(Add -x to both sides)
2
x
+
5
=
19
2
x
+
5
+
−
5
=
19
+
−
5
(Add -5 to both sides)
2
x
=
14
2
x
2
=
14
2
(Divide both sides by 2)
x
=
7
Step: Substitute
7
for
x
in
y
=
3
x
+
5
:
y
=
3
x
+
5
y
=
(
3
)
(
7
)
+
5
y
=
26
(Simplify both sides of the equation)
Answer:
x
=
7
and
y
=
26
Answer:
What is it?
Step-by-step explanation:
Answer:
6 years old
Step-by-step explanation:
First, turn the information given in words as equations. Use variables to represent the people:
let A be Addison's age
let B be Bailey's age
let C be Christopher's age
A = 3B (Addison is 3 times as old as Bailey)
B = 2.5C (Bailey is 2.5 times as old as Christopher)
A + B + C = 66 (the sum of their ages is 66) (sum means addition)
Start with the equation for the sum of their ages (A + B + C = 66). You have other equations that can replace the variables in this equation.
A + B + C = 66
(3B) + B + C = 66 Replace A with 3B (because A = 3B)
4B + C = 66 Collect like terms (3B + B = 4B)
4(2.5C) + C = 66 Replace B with 2.5C (because B = 2.5C)
10C + C = 66 Collect like terms (10C + C = 11C)
11C = 66 Isolate "C"
11C/11 = 66/11 Divide both sides by 11 to cancel out 11 on the left side.
C = 6 Christopher's Age
Therefore Christopher is 6 years old.
Answer:
x= -24
Step-by-step explanation:
-48/x= 2
-48= 2x
-48/2= x
-24= x
