# Posts by Shay

Total # Posts: 416

**algebra**

A ball is thrown straight up. Its height, h(in metres), after t seconds is given by h=-5t^2+10t+2. To the nearest tenth of a second, when is the ball 6m above the ground? Explain why there are two answers. you have to equate h to 6: h = 6 ----> 5t^2+10t+2 = 6 ---> 5 t^2...

**algebra**

Determine the value(s) of k for which x^2+(k-2)x-2k=0 has equal and real roots. a x^2 + bx + c = 0 has two different roots if the discriminant D defined as: D = b^2 - 4 a c does not equal zero. If D = 0 then there is one root. That root is then real if b/a is real. In this ...

**math**

A ball is thrown straight up. Its height, h(in metres), after t seconds is given by h=-5t^2+10t+2. To the nearest tenth of a second, when is the ball 6m above the ground? Explain why there are two answers. set h=6 rearrange the quadratic equation to get 5t^2 - 10t + 4=0 Solve ...

**can someone please help me?**

simplify the following expressions involving complex numbers. (3+2i)-(-7-i) 10 + 3i how did you do that? can you show me this one and explain how this time? (3+2i)(-7-i) or even (3-2i)^2 you would do 3+2i=5i, then -7-i=7i then 5i+7i=12i (3+2i)-(-7-i) = (3+2i) + (7 + i) = 3 + 7...

**math**

A ball is thrown straight up. Its height, h(in metres), after t seconds is given by h=-5t^2+10t+2. To the nearest tenth of a second, when is the ball 6m above the ground? Explain why there are two answers. I don't get how to calculate it. Please help. whats the question ...

**math**

simplify the following expressions involving complex numbers. (3+2i)-(-7-i) is i like x? and how would this work i know that you do this: (3+2i)(7+i) to get rid of the sign between the expressions. but then what?

**math**

simplify the following expressions involving complex numbers. (3+2i)-(-7-i) is i like x? and how would this work i know that you do this: (3+2i)(7+i) to get rid of the sign between the expressions. but then what?

**math**

A ball is thrown straight up. Its height, h(in metres), after t seconds is given by h=-5t^2+10t+2. To the nearest tenth of a second, when is the ball 6m above the ground? Explain why there are two answers. I don't get how to calculate it. Please help.

**math**

The rectangle given has a perimeter of 14 units. Find the value(s) of x by factoring a quadriatic equation. one side= 12/(x+1) other side= 6/(4-x) Remember that the perimeter of a rectangle is: P = 2L + 2W Note: P = perimeter, L = length, and W = width. Therefore: 14 = 2[12/(x...

**MATH**

find the x-intercepts of y=3x^2-6x by factoring y = 3x^2 - 6x Factor out 3x: y = 3x(x - 2) Set each factor equal to 0: 3x = 0; x = 0 x - 2 = 0; x = 2 Those are your x-intercepts. I hope this will help.

**MATH**

solve 1-(2/x)=2/(x+2) Express your answer in simplest radical form. What is radical form ne how? 1-(2/x)=2/(x+2) Multiply both sides by x(x+2): x(x+2) - 2(x+2) = 2x Note that we cannot allow x to be 0 or minus two because for these values the original equation is not defined. ...

**Math**

The ractangle given has a perimeter of 14 units. Find the value(s) of x by factoring a quadriatic equation. x= 12/(x+1) y= 6/ (4-x) If anyone can help me that would be awesome, thanks a bunch. I can only give you an example : for example x2 - x -6 = 0 solution x2 - 6 = 0 (x + ...

**algerbra**

mrs. johnson is 3 times as old as her son. ten years agoe she was 5 times as old as her son was then. what is the two equations for this problem? let x = son's age and y = Mrs. Johnson's age. ============================ y=3x is one equation. 10 years ago Mrs. Johnson...

**Algebra!**

Two cars leave the same town at the same town. One travels west at 60 mph and the other at 45 mph. In how many hours will they be 420 miles apart?

**Science**

Why must chromosomes be duplicated before mitosis? DNA is the instruction of making proteins.To have a new cell that can work, it must has a replication of DNA.

**Calculus**

Hello. I would appreciate it if someone could check my answers. I'm sorry it is so long. 1.) Let R denote the region between the curves y=x^-1 and y=x^-2 over the interval 1<= x <= 10. a. Set up an integral for the area of R. My answer: 1.403 b. Find x-bar, the x ...