Answer:
90
Step-by-step explanation:
Think of 5(18) as 5(10+8). This is easily done mentally: 50 + 40 = 90.
Answer: 7/8
Step-by-step explanation:
To find the equivalent expression of a fraction, we can either multiply numerator and denominator by same variable or same number, or we can divide both numerator and denominator by same number or same variable .
So if we multiply both numerator and denominator by 2, we will get

14 dollars . Just divide.
The quadratic equation has two solutions if b^2 - 4ac > 0
Given the equation ax^4 + bx^2 + c=0
Substitute into the formula to have:
The equation becomes aP^2 + bP + c = 0
For us to have a unique solution, the discriminant b^2 - 4ac must be greater than zero. Hence the quadratic equation has two solutions if b^2 - 4ac > 0
learn more on discriminant here; brainly.com/question/1537997