Answer:
12
Step-by-step explanation:
(a) 95 = (x+7)*(x-7)
(b) 95 = (x+7)*(x-7)
Expand the brackets:
95 = x² -7x + 7x -49 = x² - 49
Subtract x² from both sides:
95-x² = -49
Subtract 95 from both sides:
-x²=-49-95
-x²= -144
Divide both sides by -1 to get rid of the negative numbers:
-x²/-1=-144/-1
x²=144
Take the square root of 144:
x = ± squareroot of 144
x = 12 or -12
x = 12 because you cannot have a negative age so Trina is 12 years old.
The regular selling price per unit for the laptop is $298.6.
<h3>How to calculate the price?</h3>
Let the regular price per unit be x.
The expense is 19% of the selling price and profit is 25% of the selling price. This will be illustrated as:
x + (19% × x) + (25% × x) = 430
x + 0.19x + 0.25x = 440
1.44x = 430
Divide
x = 430 / 1.44
x = 298.6
The price is $298.6
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Answer:
the answer would be 2(2+11)
Step-by-step explanation:
5(a - 2b) - 3(a - 2b) |use distributive property: a(b - c) = ab - ac
= 5a - 10b - 3a + 6b
= (5a - 3a) + (-10b + 6b)
= 2a - 4b
