Since y=3x+15
sub 3x+15 for y in other equation
2x+3(3x+15)=1
2x+9x+45=1
minus 45
11x=-44
divide 11
x=-4
sub
y=3x+15
y=3(-4)+15
y=-12+15
y=3
(-4,3)
Answer:
Step-by-step explanation:
prob(grow) = .65
prob(not grow) = .35
prob(1 of 11 will not grow)
= C(11,1)(.35)(.65)^10
= .05183
Answer:
x = 1/4
Step-by-step explanation:
-7x - (-5-x) = -9(2x-1) -1
-7x + 5 + x = -18x + 9 - 1
combine like terms:
-6x + 5 = -18x + 8
add 18x to each side of the equation:
12x + 5 = 8
subtract 5 from each side:
12x = 3
divide both sides by 12:
x = 3/12 = 1/4
Answer:
90 g of water should be added and he will make 900 g of solution.
Step-by-step explanation:
Let x g be the amount of salt Ilya add to 810g of water to make 10% solution. Then 810+x g is the amount of new solution. Thus,
810+x - 100%,
x - 10%.
Mathematically,

So 90 g of water should be added and he will make 810+90=900 g of solution.