Answer:
Multiply it like a normal number.
Step-by-step explanation:
Take the point away in both numbers
line the numbers up and add the zero at the end of 28
multiply
add the decimal point back after solved (3 decimal points)
818
x280
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Answer:
30 cm^2
Step-by-step explanation:
a = 13 cm
b = 12 cm
using Pythagorean theorem:
a^2 = b^2 + c^2
--> c^2 = a^2 - b^2 = 13^2 - 12^2 = 169 - 144 = 25
--> c = √25 = 5
The area of that right triangle is:
S = b.c / 2 = 12 . 5 / 2 = 30 (cm^2)
Answer:
x= -13
y= -28
Step-by-step explanation:
To find the two numbers, write a system of equations with x as one number and y as another:
x-y=15
5x=2y-9
Use substitution to substitute one equation into another. Then solve for the variable.
x=15+y into 5x=2y-9
becomes
5(15+y) = 2y-9
75+5y = 2y- 9
75+3y= -9
3y = -84
y= -28
To find x, substitute y= -28 into one equation.
x - (-28) = 15
x+28 =15
x = 15-28
x=-13
Use distributive method
5r - 50 = -51
Add 50
5r = -1
Divide by 5
r = -1/5
