Respuesta :
To solve this word problem, we are going to write a system of equations, letting the variable a represent Andre's test score, and the variable b represent Brandon's test score.
We know that Andre and Brandon's combined test score is 180, or
a+b = 180
We also know that Andre's score is twice as much as 30 less than Brandon's score, or
2a = b - 30
Now, we just need to solve the system of equations by substitution, as this is the easiest method for this specific problem.
When simplified, a+b=180 equals a=180-b
Now, if we use this equation of a in substitution for the other equation, we will get our answer.
2(180-b) = b-30
When we use the distributive property to simplify the left side of the equation, we get:
360-2b=b-30
When we further reduce the equation by adding 2b to both sides of the equation, we get:
360 = 3b-30
Next, we have to add 30 to both sides to get the variable alone on the right side of the equation, resulting in the equation:
390=3b
Finally, we divide both sides by 3 to separate the coefficient from the variable b
130=b
Now, we have to substitute our solution for the variable b into the original equation.
a+b=180
a+130=180
a=50
Therefore, Brandon's test score was 130, and Andre's test score was 50.
We know that Andre and Brandon's combined test score is 180, or
a+b = 180
We also know that Andre's score is twice as much as 30 less than Brandon's score, or
2a = b - 30
Now, we just need to solve the system of equations by substitution, as this is the easiest method for this specific problem.
When simplified, a+b=180 equals a=180-b
Now, if we use this equation of a in substitution for the other equation, we will get our answer.
2(180-b) = b-30
When we use the distributive property to simplify the left side of the equation, we get:
360-2b=b-30
When we further reduce the equation by adding 2b to both sides of the equation, we get:
360 = 3b-30
Next, we have to add 30 to both sides to get the variable alone on the right side of the equation, resulting in the equation:
390=3b
Finally, we divide both sides by 3 to separate the coefficient from the variable b
130=b
Now, we have to substitute our solution for the variable b into the original equation.
a+b=180
a+130=180
a=50
Therefore, Brandon's test score was 130, and Andre's test score was 50.
Answer: Brandon's score x= 80
Andre's score=100
Step-by-step explanation:
Let 'x' represents Brandon's score in math quiz.
Then, Andre's score =2(x-30)
Since, the sum of Andre and Brandon's scores on a math quiz is 180.
Then, [tex]x+2(x-30)=180[/tex]
[tex]x+2x-60=180\\\\\Rightarrow3x=180+60\\\\\Rightarrow3x=240\\\\\Rightarrow x=80[/tex]
Therefore, Brandon's score x= 80
Andre's score [tex]=2(80-30)=2(50)=100[/tex]