the weight of the substance after 28 years is 8 grams.
<h3>How to determine the amount</h3>
We have that the half life of a substance is defined as the time required for the substance to decrease by half
The formula for calculating the half - life of a material is given as;
Where
- N(t) is final amount
- No is the initial amount = 128 grams
- t1/2 is the half life = 7 years
- t is the time elapsed = 28 years
Substitute into the formula
N(t) = 128 × (0. 5) ^28/ 7
N (t) = 128 × ( 0. 5) ^ 4
N(t) = 128 × 0. 0625
N(t) = 8 grams
Thus, the weight of the substance after 28 years is 8 grams.
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Draw a cartesian plane, create a graph with the equation x = y^2 - 2
then substitute numbers into the equation so that it is true, to find points on the graph, e.g. substitute y with 1, you get
x = 1^2 - 2
x = 1 - 2 = -1, so when y = 1, x = -1, this point is (-1, 1)
for the next substitute y with 2,
x = 2^2 - 2
x = 4 - 2 = 2, the point is (2, 2)
you might want to try negative values of y
y = -1, x = (-1)^2 - 2
x = -1 the point is (-1,-1)
then plot the points on the graph
Answer:
Given: In triangle ABC and triangle DBE where DE is parallel to AC.
In ΔABC and ΔDBE
[Given]
As we know, a line that cuts across two or more parallel lines. In the given figure, the line AB is a transversal.
Line segment AB is transversal that intersects two parallel lines. [Conclusion from statement 1.]
Corresponding angles theorem: two parallel lines are cut by a transversal, then the corresponding angles are congruent.
then;
and
Reflexive property of equality states that if angles in geometric figures can be congruent to themselves.
by Reflexive property of equality:
By AAA (Angle Angle Angle) similarity postulates states that all three pairs of corresponding angles are the same then, the triangles are similar
therefore, by AAA similarity postulates theorem
Similar triangles are triangles with equal corresponding angles and proportionate side.
then, we have;
[By definition of similar triangles]
therefore, the missing statement and the reasons are
Statement Reason
3. Corresponding angles theorem
and
5. AAA similarity postulates
6. BD over BA Definition of similar triangle
Answer:
1.B not sure about 2 though sorry i couldnt help u on 2 Step-by-step explanation:
