Last question xd
answer asap!
3x - 5y = 10
6x + 3y = -6

marybeth is going to solve this problem by multiplying the top equation by -2. if she does this and combines the equations, what does she get?
a) -13y = -26
b) -7y = 14
c) -2y = 4
d) 13y = -26

The answer to your question is letter D.

Step-by-step explanation:

                                            3x - 5y =  10         (1)

                                            6x + 3y = -6         (2)

Following directions

                                     -2( 3x - 5y = 10)

                                          6x + 3y = -6

Expanding

                                         -6x + 10y = -20

                                          6x +  3y  = -6

Simplifying

                                           0 + 13y = -26

                                                 13y = -26                                                        

                                                     y = -26/ 13

                                                     y = -2

hello,

b) 62.47% of the students are between 14 and 18 years old.

step-by-step explanation:

mean = 15 and standard deviation = 2

student between 14 to 18

formula used z-score

for age 14 , z score

using z-table , p(z> -0.5)=0.3085

for age 18 , z score

using z-table , p(z< 1.5)=0.9332

p(-0.5< z< 1.5)=0.9332-0.3085 = 0.6247

thus, 62.47% of the students are between 14 and 18 years old.

click to let others know, how is it

0.0

0 votes

1

report

read more on -

step-by-step explanation: