Answer:
Therefore,
.......Equation
Angelica's Brother's age is 11 years old.
Step-by-step explanation:
Given:
Let the current age of Angelica's Brother be 'x' years old
Angelica's current age is 13 years old,
According to given condition,
Therefore the Equation will be,

On solving this equation we get

Therefore,
Angelica's Brother's age is 11 years old.
Therefore,
.......Equation
Angelica's Brother's age is 11 years old.
Step-by-step explanation:
this is really simple : we only need to put the given x and y coordinate values into both equations and see, if both equations remain true.
(-2, -1) means x = -2, y = -1
first equation :
-1 = 3×-2 + 5 = -6 + 5 = -1
so, -1 = -1
true.
second equation :
-2 + -1 = -3
-3 = -3
true.
therefore, (-2, -1) is a solution to the linear system.
the point is the crossing point of both lines.
You solve for y so then u subtract the 7x from 30 to get 30-7x equals -10 since the -10 has a variable it means u divide by -10 to the subtracting equation to get-3+7/10
Answer:
$550+/-$20.79
= ( $529.21, $570.79)
Therefore, the 95% confidence interval (a,b) = ( $529.21, $570.79)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = $550
Standard deviation r = $75
Number of samples n = 50
Confidence interval = 95%
z(at 95% confidence) = 1.96
Substituting the values we have;
$550+/-1.96($75/√50)
$550+/-1.96($10.60660171779)
$550+/-$20.7889393668
$550+/-$20.79
= ( $529.21, $570.79)
Therefore, the 95% confidence interval (a,b) = ( $529.21, $570.79)