Answer:
(-1/4, 19/4)
Step-by-step explanation:
5x+6=9x+7
-4x=1
x= -1/4
y=5(-1/4) +6
y=19/4
Answer:
She didn't put the sign's in the proper place, it should be ( x + 3 ) ( x - 7 )
Step-by-step explanation:
( x - 3 ) ( x + 7 ) = x² + 7x - 3x - 21 = x² + 4x - 21
( x + 3 ) ( x - 7 ) = x² - 7x + 3x - 21 = x² - 4x - 21
Answer:

Step-by-step explanation:
Let
x -----> the number of ice cream cones sold 5 years ago
Remember that

we know that
Sales 5 years ago, multiplied by the 30% increase should equal 18,000 ice cream cones.
so
The linear equation that represent this problem is

Solve for x
Divide by 1.3 both sides

Answer:
H0 : mu1 = mu2
Ha : mu1 ≠ mu2
Which means
Null hypothesis H0; the true mean price when buying from a friend mu1 and the true mean price when buying from a stranger mu2 is the same/equal
Alternative hypothesis Ha; the true mean price when buying from a friend mu1 and the true mean price when buying from a stranger mu2 is different (not equal)
Step-by-step explanation:
The null hypothesis (H0) tries to show that no significant variation exists between variables or that a single variable is no different than its mean(i.e it tries to prove that the old theory is true). While an alternative Hypothesis (Ha) attempt to prove that a new theory is true rather than the old one. That a variable is significantly different from the mean.
Therefore, for the case above;
H0 : mu1 = mu2
Ha : mu1 ≠ mu2
Which means
Null hypothesis H0; the true mean price when buying from a friend mu1 and the true mean price when buying from a stranger mu2 is the same/equal
Alternative hypothesis Ha; the true mean price when buying from a friend mu1 and the true mean price when buying from a stranger mu2 is different (not equal)
The answer would just be 3xy since you can take out 3 and one x and a y