5x^2+3x-4=0
<span>x^2+3x/5-4/5=0 </span>
<span>x^2+3x/5=4/5 </span>
<span>x^2+3x/5+9/100=89/100 </span>
<span>(x+3/10)^2=89/100 </span>
<span>x+3/10=±(√89)/10 </span>
<span>x=-3/10±√89/100 </span>
<span>x=-3±(√89/10)</span>
Answer:
Step-by-step explanation:
we know that
----> by trigonometric identity
we have
substitute
Remember that
If the sine of angle theta is positive, then the angle theta lie on the I Quadrant or II Quadrant
therefore
If the angle theta is on the I Quadrant the cosine will be positive
If the angle theta is on the II Quadrant the cosine will be negative
Answer:
$1.25
Step-by-step explanation:
This can best be determined using a set of linear equations that are solved simultaneously.
This pair of linear equations may be solved simultaneously by using the elimination method. This will involve ensuring that the coefficient of one of the unknown variables is the same in both equations.
Let the cost of a cookie be c, cost of a doughnut be d and that of a box of doughnut hole be h then if cost of 4 cookies, 6 doughnuts, and 3 boxes of doughnut holes is $8.15, we have
4a + 6d + 3h = 8.15
and the cost of 2 cookies, 3 doughnuts, and 4 boxes of doughnuts holes is $7.20 then
2a + 3d + 4h = 7.20
Dividing the first by 2
2a + 3d + 1.5h = 4.075
subtracting from the second equation
2.5h = 3.125
h = 1.25
The cost of a box of doughnut holes is $1.25