In a quadratic equation of the form (ax^2 + bx + c), the discriminant is equal to (b^2 - 4ac).
So for the first question it would be
4^2 - 4*(6*-2) = 64
Second question (-7)^2 - 4*(9*5) = -131
You can do the rest.
Answer: the cost of one shirt is $28
the cost of one sweater is $23
Step-by-step explanation:
Let x represent the cost of one shirt.
Let y represent the cost of one sweater.
Lonnie purchased three sweaters and two shirts for $130. It means that
2x + 3y = 130 - - - - - - - - -1
If the sale price of a shirt was five dollars less than the sale price of a sweater, it means that
x = y - 5
Substituting x = y - 5 into equation 1, it becomes
2(y - 5) + 3y = 130
2y - 10 + 3y = 130
2y + 3y = 130 + 10
5y = 140
y = 140/5
y = 28
x = y - 5 = 28 - 5
x = 23
21x - 14y
7(3x) - 7(2y)
7(3x - 2y)
Hope you can see my working that is attached below.
<span>the side length of the smallest square plate on which a 26-cm chopstick can fit along a diagonal without an overhang is
18.38 cm long (to 2 d.p.) or if you want a more accurate answer you can leave the answer in surds for as
13</span>
cm
One person. A 30 gram stone is very light.