Answer:
1. AC is perpendicular to BD
1. Given
2. ACB is a right angle
2. Definition of perpendicular lines
3. Triangle ACB is a right triangle
3. Definition of right triangles
4. Angles 1 and 3 are complementary
4. Interior angles of a triangle add up to 180 degrees (Triangle Interior Angle Sum Theorem), and m<ACB = 90 degrees (definition of right angles), so m<1 + m<3 = 90 degrees (subtraction property of equality). By the definition of complementary angles, angles 1 and 3 are complementary.
Answer: Yes, Daniel has enough money to buy 2 pens.
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Explanation:
x = cost of one pencil
y = cost of one pen
4x = cost of 4 pencils
3y = cost of 3 pens
4x+3y = cost of 4 pencils and 3 pens
100 - (4x+3y) = amount Daniel has left = 7 dollars
100-(4x+3y) = 7 is one equation we can form
Another equation we can form is x = y+3 because "each pencil costs $3 more than each pen".
Let's plug that into the first equation and solve for y.
100-(4x+3y) = 7
100-(4(y+3)+3y) = 7
100 - (4y+12+3y) = 7
100 - (7y+12) = 7
100 - 7y - 12 = 7
-7y + 88 = 7
-7y = 7-88
-7y = -81
y = -81/(-7)
y = 11.57 is the cost of one pen
2y = 2*11.57 = 23.14 is the cost of two pens.
Since this is less than $25, this means he has enough to buy two pens. This assumes that we either ignore tax, or the tax is already included in the listed prices.
Let n be the common factor for the ratio 6:5. Then:
6n+5n=330
11n=330
n=30
aerobics=6n=180 min
weight training=5n=150 min
☺☺☺☺
Distance between the lower and upper grade
Answer:
less than
Step-by-step explanation:
