Let the required number is 2x ,
According to the condition,
➡ 10 times the sum of half of 2x and 6 = 8
Therefore the value of x is -5.2
And, required number is -5.2
#1)
Answer:
x=1 and y=12
Explanation:
y=5x+7
y=2x+10
This system should use substitution because the value of y is given in terms if x.
Substitution:
5x+7=2x+10
Solve:
3x=3
x=1
Substitute x to solve for y by plugging x into one if the original equations(doesn’t matter which one is used).
y=5x+7
y=5(1)+7
y=5+7
y=12
#2)
Answer:
x=-8 and y=2
Explanation:
y=2x+18
9y=-2x+2
This system also uses substitution. The value of y us already given in terms if c in the first equations, so we will substitute in the second equation.
Substitute:
9(2x+18)=-2x+2
Solve:
18x+162=-2x+2
20x=-160
x=-8
Now that we have the value if x, plug it into one of the original equations(doesn’t matter which equation) and substitute to find y.
y=2x+18
Substitute:
y=2(-8)+18
Solve:
y=-16+18
y=2
Answer:
x=2 and y=1
Step-by-step explanation:
Rewrite equations:
y=−x+3;y=x−1
Step: Solve
y=−x+3
Step: Substitute−x+3foryiny=x−1:
y=x−1
−x+3=x−1
−x+3+−x=x−1+−x(Add -x to both sides)
−2x+3=−1
−2x+3+−3=−1+−3(Add -3 to both sides)
−2x=−4−2x−2=−4−2
(Divide both sides by -2)
x=2
Step: Substitute2forxiny=−x+3:
y=−x+3
y=−2+3
y=1(Simplify both sides of the equation)
Hope this Helps you :)
The answer is E.90
1/2 inches = 10 miles
9(1/2) inches = 4 1/2 inches
9(10) miles = 90 miles
