geno3141

5 x 198  =  5 x (200 - 2)  =  5 x 200 - 5 x 2  =  1000 - 10  =  990

For negative numbers, the one closest to 0 is the largest.

-30 is closer to 0 than -47; therefore -30 is the larger number.

If you know that  x = 45,  then  x + 65  =  45 + 65  =  110

Starting with:                                      y + 1/5  =  3x

Subtract 3x from both sides:  -3x + y + 1/5  =  0

Subtract 1/5 from both sides:           -3x + y  =  -1/5

Multiply both sies by 5:                    -15x + 5y  =  -1      

To find the x-intercept, replace y with 0 and solve:  y  =  -(1/2)x - 3

                                                                                       0  =  -(1/2)x - 3

                                                                                       3  =  -(1/2)x

                                                                                      -6  =  x     --->     (-6, 0)

To find the y-intercept, replace x with 0 and solve:  y  =  -(1/2)x - 3

                                                                                       y  =  -(1/2)(0) - 3

                                                                                       y  =  -3     --->     (0, -3)

When the football hits the ground, the value of h will be 0.

Solving:  -16t² + 36t + 4  =  0

Using the quadratic formula with  a = -16   b = 36   c = 4:

t  =  [ -36 +/- sqrt( 36² - 4(-16)(4) ) ] / [ 2(-16) ]

t  =  [ -36 +/- sqrt( 1296 + 256 ) ] / [ -32 ]

t  =  [ -36 +/- sqrt( 1552 ) ] / [ -32 ]

t  =  [ -36 +/- sqrt(16)·sqrt(97) ] / [ -32 ]

t  =  [ -36 +/- 4·sqrt(97) ] / [ -32 ]

Dividing numerator and denominator by -4:

t  =  [ 9 +/- sqrt(97) ] / 8

Answer C.

By saying "125% more time", he is saying that the extra time he spent was 125% of the orginal amount.

Last week he spent 20 hours. This week, he spent 25 hours, 5 more hours.

Comparing the extra hours (5) to the hours that he spent last week (20):  5/20  =  25% extra time.

The hours that he spent this week, when compared to the hours last week, is 125%; but this isn't 125% more time.  

The formula can be found at:  http://keisan.casio.com/exec/system/14059932254941

This also contains a calculator that applies it.

5 · 3 - (-2 · -7)  =  15 - (14)  =  1

(-7 - 5) / (-2 · 3)  =  -12 / -6  =  2

5 / ( 3 · -2 - -7 )  =  5 / ( -6 + 7 )  =  5 / 1  =  5

-(-7) - ( 3 · -2 + 5 )  =  7 - ( -6 + 5 )  =  7 - (-1)  =  8

                                                      20 000  =  17 000(1 + r)⁵

Flip sides:                         17 000(1 + r)⁵  =  20 000

Divide both sides by 17 000:     (1 + r)⁵  =  20 000 / 17 000

Find the fifth root of both sides:     1 + r  =  (20 000 / 17 000)^1/5

Subtract 1:                                             r  =  (20 000 / 17 000)^1/5 - 1

Calculator time!