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:
10.5 ft
Step-by-step explanation:
In ΔQRS,
- m∠S=90°
- m∠R=29°,
- SQ = 5.8 feet.
See the diagram below.
The triangle is a Right Triangle,
Using trigonometric ratios,
Answer:
Step-by-step explanation:
Stephen uses 
kilograms of tofu in each serving of his dish.
He has 
kilograms of tofu.
We want to determine how many servings Stephen can make.
To do this, we divide the total weight of tofu by the weight per serving.
Stephen can make .
Answer:
44.49
Step-by-step explanation:
just add all the values
5+9.71+14.1+15.68=44.49
1. The correct statement is the first one, which is: <span>Add the two equations, solve for y, and then substitute –1 for y to find x.
</span>
2. Therefore, you have the following system of equations:
<span>
4x+8y=20
-4x+2y= -30
3. When you a</span>dd the two equations, and clear the variable "y", you obtain:
10y=-10
y=-1
4. Now, you must substitute -1 for y (y=-1) to find x, as below:
4x+8y=20
4x+8(-1)=20
4x-8=20
4x=20+8
4x=28
x=28/4
x=7
