Let's solve your system by substitution.
y
=
−
2
x
+
7
;
y
=
5
x
−
7
Step: Solve
y
=
−
2
x
+
7
for y:
y
=
−
2
x
+
7
Step: Substitute
−
2
x
+
7
for
y
in
y
=
5
x
−
7
:
y
=
5
x
−
7
−
2
x
+
7
=
5
x
−
7
−
2
x
+
7
+
−
5
x
=
5
x
−
7
+
−
5
x
(Add -5x to both sides)
−
7
x
+
7
=
−
7
−
7
x
+
7
+
−
7
=
−
7
+
−
7
(Add -7 to both sides)
−
7
x
=
−
14
−
7
x
−
7
=
−
14
−
7
(Divide both sides by -7)
x
=
2
Step: Substitute
2
for
x
in
y
=
−
2
x
+
7
:
y
=
−
2
x
+
7
y
=
(
−
2
)
(
2
)
+
7
y
=
3
(Simplify both sides of the equation)
Answer: x=2 and y=3
Answer:
3 - x ≥ 9
Step-by-step explanation:
At least in inequality means greater than or equal to (≥)
Difference in mathematics means subtraction
The difference between a number x and 3
3 - x
is at least nine
3 - x ≥ 9
The inequality for the sentence is
3 - x ≥ 9
1- 0.25= 0.75 (multiplier)
33÷0.75=44
The suitcase originally weighed 44kg
Hope this helps!
Answer:
Step-by-step explanation:
Hello, I believe that we can consider a different from 0.
By definition of the roots we can write.

Thank you