1. Find the domain of y=x+3 if the range is {-1,1,3,5}?

1. Find the domain of y=x+3 if the range is {-1,1,3,5}





2. A lake is 120 fathoms deep. use the fast that there are 6 feet in a fathom to tell the depth of the lake in feet





3. Suppose y varies inversely as x and y= 5 when x=20


find x when y=2


write an equation of the line in slope-intercept form with slope 1/3 that crosses the y-axis at (0, -2)





4. Find the product: -5a 2 (a 2 - 6a + 7)





5. Find the product:(6y + 5)(2y + 3)





6. Factor the polynomial s 2 + 25. if the polynomial


cannot be factored, write prime





7. Find the roots of 2x 2 - 5x + 1 = 0





8. Find the value of c to make g 2 - 18g + c s perfect


square

1. Find the domain of y=x+3 if the range is {-1,1,3,5}?
1) range is the x values and domain is the y values. so the range actually you can just state as -1≤ x ≤ 5. substitute the values x=-1 and x=5 into the equation to get the y values which are 2 and 8 respectively. therefore the domain is 2≤ y ≤8





2) 6 feet in one fanthom so in 120 fanthoms will be just 6 times 120 which will give 720 feet.





3) let constant be k


y varies inversely as x means y=k/x


substitute y=5 and x=20 in the equation to find the value of the constant which is x here. the value of k is 100. then the equation will be y=100/x. to find x when y=2, just substitute in y=2 into the equation then you will be able to find x which is 50.


when u say with slope 1/3 i take it that it is the gradient?


for a normal equation, the equation is y=mx + c where m is the gradient and c is the constant. sub m=1/3 to get y=x/3 + c. Then substitute the values x=0,y=-2 to find the value of constant c. c= -2. therefore u substitute in m=1/3 and c=-1, the equation of the line is y=x/3 - 2.





4) i assume that -5a 2 is -5asquare. (a^2 is a to the power of 2 in other words a square)


-5a^2 (a^2 - 6a +7) = (-5a^2 x a^2) + (-5a^2 x -6a) + (7 x -5a^2) = -5a^4 + 30a^3 - 35a^2





5) (6y+5)(2y+3) = (6y x 2y) + (6y x 3) + (5 x 2y) + (5 x 3) = 12y^2 + 18y +10y+15 = 12y^2 + 28y +15





6) I am not sure what the question wants me to do (sorry)





7) 2x^2 - 5x +1. Factorise this equation using general equation. (search for this term online because i do not know how to explain it here.) x=2.28 , 0.219





8) I am not sure what the question wants me to do. (sorry)

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