Math Is Fun Forum

rewrite the equation 4x - 10y = 11 as a function of x

a. y= -2/5x + 11

b. y=2/5x-11

c. y = 2/5x -11/10

d. y = -2/5x + 11/10

this is my thinking 10y = 4/10x + 11/10
                             y =2/5x + 11/10
                             correct??

write equation of the line with slope 4 and y-intercept (0.-5)

y-(-5)=4(x-0); y+5 = 4x - 0 ; y=4x-5 correct??

first one -6x=6; x=-1 correct?

and
4(7x+10) = 3(9x-5)+20
28x+40 = 27x-15+20
x=-35 correct??

company produces scarves and sweaters; scarves take 2 hours to produce and sweaters take 14 hours to produce; available labor is 40 hours per week; total productions capacity is 5 items per week; write a system of inequalities representing the situation; where x is number of scarves and y is the number of sweaters; then graph the inequalities.   I am thinking x+y<=5 and 2+ 14 <40 is this anywhere near correct???

solve the system by substitution

3x + 6y =o; x=2/3; 3(2/3) +6y =0; 2+ 6 = ) confused???

3x - y = -7 ; x + y = -9; y= -x-9;  3x -x = -7; 2x = -7; x = -7/2 now I'm confused again what in the world am I doin??

3x+y<=5 it says graph the inequality

f(x)=5xsqured -3x+1findf(-2)
f(-2)=5(-2)squared - 3(-2) +1
  5(4)-3(-2)+1=20-(-6)+1=14+1=15 correct?

one number is 12 more than another. the sum of the smaller number and twice the larger number is 39. find the larger number.
x-12=n
n+2(x)=39 am I on the right track?