The problem
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how can I solve an algebraic expression here? for example:
Evaluate the expressions when y+-7
y^+4y-1
The answer is supposed to be Y=20 but couldn't get it here. Thanks
Answer provided by our tutors
To evaluate an algebraic expression, you have to substitute a number for each variable and perform the arithmetic operations.
y^2+4y-1
For y = 7 we get:
7^2+4*7-1=49+28-1 - 76
For y = -7 we get:
(-7)^2+4*(-7)-1=49-28-1 = 20